1625281 has 12 divisors (see below), whose sum is σ = 1939140. Its totient is φ = 1357440.

The previous prime is 1625263. The next prime is 1625287. The reversal of 1625281 is 1825261.

It can be written as a sum of positive squares in 2 ways, for example, as 705600 + 919681 = 840^2 + 959^2 .

It is not a de Polignac number, because 1625281 - 2⁷ = 1625153 is a prime.

It is a super-2 number, since 2×1625281² = 5283076657922, which contains 22 as substring.

1625281 is a Rhonda number in base 16.

1625281 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1625287) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1605 + ... + 2413.

It is an arithmetic number, because the mean of its divisors is an integer number (161595).

2^1625281 is an apocalyptic number.

It is an amenable number.

1625281 is a deficient number, since it is larger than the sum of its proper divisors (313859).

1625281 is an equidigital number, since it uses as much as digits as its factorization.

1625281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864 (or 857 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The square root of 1625281 is about 1274.8650909018. The cubic root of 1625281 is about 117.5735106626.

It can be divided in two parts, 16 and 25281, that multiplied together give a square (404496 = 636²).

The spelling of 1625281 in words is "one million, six hundred twenty-five thousand, two hundred eighty-one".