25643481 has 8 divisors (see below), whose sum is σ = 34575840. Its totient is φ = 16903392.

The previous prime is 25643441. The next prime is 25643489. The reversal of 25643481 is 18434652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 25643481 - 2⁷ = 25643353 is a prime.

It is a super-2 number, since 2×25643481² = 1315176235594722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25643489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47755 + ... + 48288.

It is an arithmetic number, because the mean of its divisors is an integer number (4321980).

Almost surely, 2^25643481 is an apocalyptic number.

It is an amenable number.

25643481 is a deficient number, since it is larger than the sum of its proper divisors (8932359).

25643481 is an equidigital number, since it uses as much as digits as its factorization.

25643481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96135.

The product of its digits is 23040, while the sum is 33.

The square root of 25643481 is about 5063.9392768871. The cubic root of 25643481 is about 294.8892852753.

The spelling of 25643481 in words is "twenty-five million, six hundred forty-three thousand, four hundred eighty-one".