25400 has 24 divisors (see below), whose sum is σ = 59520. Its totient is φ = 10080.

The previous prime is 25391. The next prime is 25409. The reversal of 25400 is 452.

25400 = T₃₂ + T₃₃ + ... + T₅₆.

It is an interprime number because it is at equal distance from previous prime (25391) and next prime (25409).

It is a sliding number, since 25400 = 400 + 25000 and 1/400 + 1/25000 = 0.0025400.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 137 + ... + 263.

It is an arithmetic number, because the mean of its divisors is an integer number (2480).

2²⁵⁴⁰⁰ is an apocalyptic number.

25400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29760).

25400 is an abundant number, since it is smaller than the sum of its proper divisors (34120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25400 is a wasteful number, since it uses less digits than its factorization.

25400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 11.

The square root of 25400 is about 159.3737745051. The cubic root of 25400 is about 29.3953005894.

Adding to 25400 its reverse (452), we get a palindrome (25852).

It can be divided in two parts, 25 and 400, that multiplied together give a 4-th power (10000 = 10⁴).

The spelling of 25400 in words is "twenty-five thousand, four hundred".