25651616440521 has 32 divisors (see below), whose sum is σ = 37778469442560. Its totient is φ = 15426208252224.

The previous prime is 25651616440507. The next prime is 25651616440589. The reversal of 25651616440521 is 12504461615652.

It is a happy number.

It is not a de Polignac number, because 25651616440521 - 2¹³ = 25651616432329 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25651616040521) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148976731 + ... + 149148816.

It is an arithmetic number, because the mean of its divisors is an integer number (1180577170080).

Almost surely, 2^{25651616440521} is an apocalyptic number.

It is an amenable number.

25651616440521 is a deficient number, since it is larger than the sum of its proper divisors (12126853002039).

25651616440521 is a wasteful number, since it uses less digits than its factorization.

25651616440521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298125645.

The product of its (nonzero) digits is 1728000, while the sum is 48.

The spelling of 25651616440521 in words is "twenty-five trillion, six hundred fifty-one billion, six hundred sixteen million, four hundred forty thousand, five hundred twenty-one".