25700021951 has 2 divisors, whose sum is σ = 25700021952. Its totient is φ = 25700021950.

The previous prime is 25700021917. The next prime is 25700021959. The reversal of 25700021951 is 15912000752.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25700021951 - 2⁶ = 25700021887 is a prime.

It is a super-2 number, since 2×25700021951² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25700021959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12850010975 + 12850010976.

It is an arithmetic number, because the mean of its divisors is an integer number (12850010976).

Almost surely, 2^25700021951 is an apocalyptic number.

25700021951 is a deficient number, since it is larger than the sum of its proper divisors (1).

25700021951 is an equidigital number, since it uses as much as digits as its factorization.

25700021951 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6300, while the sum is 32.

The spelling of 25700021951 in words is "twenty-five billion, seven hundred million, twenty-one thousand, nine hundred fifty-one".