25971493969 has 4 divisors (see below), whose sum is σ = 25972151296. Its totient is φ = 25970836644.

The previous prime is 25971493957. The next prime is 25971493987. The reversal of 25971493969 is 96939417952.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25971493969 - 2¹⁷ = 25971362897 is a prime.

It is a super-2 number, since 2×25971493969² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25971493969.

It is not an unprimeable number, because it can be changed into a prime (25971493369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 265329 + ... + 349774.

It is an arithmetic number, because the mean of its divisors is an integer number (6493037824).

Almost surely, 2^25971493969 is an apocalyptic number.

It is an amenable number.

25971493969 is a deficient number, since it is larger than the sum of its proper divisors (657327).

25971493969 is an equidigital number, since it uses as much as digits as its factorization.

25971493969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657326.

The product of its digits is 33067440, while the sum is 64.

The spelling of 25971493969 in words is "twenty-five billion, nine hundred seventy-one million, four hundred ninety-three thousand, nine hundred sixty-nine".