21425355171625 has 16 divisors (see below), whose sum is σ = 27901401660288. Its totient is φ = 16395054390000.

The previous prime is 21425355171613. The next prime is 21425355171643. The reversal of 21425355171625 is 52617155352412.

It is not a de Polignac number, because 21425355171625 - 2⁵ = 21425355171593 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3726145851 + ... + 3726151600.

It is an arithmetic number, because the mean of its divisors is an integer number (1743837603768).

Almost surely, 2^{21425355171625} is an apocalyptic number.

21425355171625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21425355171625 is a deficient number, since it is larger than the sum of its proper divisors (6476046488663).

21425355171625 is an equidigital number, since it uses as much as digits as its factorization.

21425355171625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7452297489 (or 7452297479 counting only the distinct ones).

The product of its digits is 2520000, while the sum is 49.

The spelling of 21425355171625 in words is "twenty-one trillion, four hundred twenty-five billion, three hundred fifty-five million, one hundred seventy-one thousand, six hundred twenty-five".