25491693240 has 96 divisors (see below), whose sum is σ = 89220942720. Its totient is φ = 6274877184.

The previous prime is 25491693209. The next prime is 25491693257. The reversal of 25491693240 is 4239619452.

25491693240 is a `hidden beast` number, since 2 + 549 + 1 + 69 + 3 + 2 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2718792 + ... + 2728151.

It is an arithmetic number, because the mean of its divisors is an integer number (929384820).

Almost surely, 2^25491693240 is an apocalyptic number.

25491693240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25491693240 is an abundant number, since it is smaller than the sum of its proper divisors (63729249480).

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

25491693240 is a wasteful number, since it uses less digits than its factorization.

25491693240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5446973 (or 5446966 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The spelling of 25491693240 in words is "twenty-five billion, four hundred ninety-one million, six hundred ninety-three thousand, two hundred forty".