25714517921 has 2 divisors, whose sum is σ = 25714517922. Its totient is φ = 25714517920.

The previous prime is 25714517911. The next prime is 25714517989. The reversal of 25714517921 is 12971541752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24739829521 + 974688400 = 157289^2 + 31220^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25714517921 is a prime.

It is a super-2 number, since 2×25714517921² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25714517911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12857258960 + 12857258961.

It is an arithmetic number, because the mean of its divisors is an integer number (12857258961).

Almost surely, 2^25714517921 is an apocalyptic number.

It is an amenable number.

25714517921 is a deficient number, since it is larger than the sum of its proper divisors (1).

25714517921 is an equidigital number, since it uses as much as digits as its factorization.

25714517921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 176400, while the sum is 44.

The spelling of 25714517921 in words is "twenty-five billion, seven hundred fourteen million, five hundred seventeen thousand, nine hundred twenty-one".