25721464761 has 16 divisors (see below), whose sum is σ = 38187489600. Its totient is φ = 17110916064.

The previous prime is 25721464709. The next prime is 25721464771. The reversal of 25721464761 is 16746412752.

25721464761 is a `hidden beast` number, since 2 + 572 + 1 + 4 + 6 + 4 + 76 + 1 = 666.

It is not a de Polignac number, because 25721464761 - 2¹⁴ = 25721448377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25721464771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1007356 + ... + 1032573.

It is an arithmetic number, because the mean of its divisors is an integer number (2386718100).

Almost surely, 2^25721464761 is an apocalyptic number.

It is an amenable number.

25721464761 is a deficient number, since it is larger than the sum of its proper divisors (12466024839).

25721464761 is a wasteful number, since it uses less digits than its factorization.

25721464761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2040405 (or 2040399 counting only the distinct ones).

The product of its digits is 564480, while the sum is 45.

The spelling of 25721464761 in words is "twenty-five billion, seven hundred twenty-one million, four hundred sixty-four thousand, seven hundred sixty-one".