25397840688 has 80 divisors (see below), whose sum is σ = 71617951872. Its totient is φ = 7691776000.

The previous prime is 25397840687. The next prime is 25397840701. The reversal of 25397840688 is 88604879352.

It is a Cunningham number, because it is equal to 159367²-1.

It is a super-2 number, since 2×25397840688² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25397840681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 942928 + ... + 969488.

Almost surely, 2^25397840688 is an apocalyptic number.

It is an amenable number.

25397840688 is an abundant number, since it is smaller than the sum of its proper divisors (46220111184).

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

25397840688 is a wasteful number, since it uses less digits than its factorization.

25397840688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28394 (or 28388 counting only the distinct ones).

The product of its (nonzero) digits is 23224320, while the sum is 60.

The spelling of 25397840688 in words is "twenty-five billion, three hundred ninety-seven million, eight hundred forty thousand, six hundred eighty-eight".