25701497991 has 48 divisors (see below), whose sum is σ = 43559370400. Its totient is φ = 14885876736.

The previous prime is 25701497963. The next prime is 25701497993. The reversal of 25701497991 is 19979410752.

It is not a de Polignac number, because 25701497991 - 2¹¹ = 25701495943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25701497993) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25246 + ... + 228123.

Almost surely, 2^25701497991 is an apocalyptic number.

25701497991 is a deficient number, since it is larger than the sum of its proper divisors (17857872409).

25701497991 is a wasteful number, since it uses less digits than its factorization.

25701497991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253425 (or 253402 counting only the distinct ones).

The product of its (nonzero) digits is 1428840, while the sum is 54.

The spelling of 25701497991 in words is "twenty-five billion, seven hundred one million, four hundred ninety-seven thousand, nine hundred ninety-one".