421520166025 has 24 divisors (see below), whose sum is σ = 599918102784. Its totient is φ = 287801846400.

The previous prime is 421520165903. The next prime is 421520166073. The reversal of 421520166025 is 520661025124.

It is not a de Polignac number, because 421520166025 - 2²⁵ = 421486611593 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5128081 + ... + 5209630.

It is an arithmetic number, because the mean of its divisors is an integer number (24996587616).

Almost surely, 2^421520166025 is an apocalyptic number.

It is an amenable number.

421520166025 is a deficient number, since it is larger than the sum of its proper divisors (178397936759).

421520166025 is a wasteful number, since it uses less digits than its factorization.

421520166025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10337961 (or 10337956 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 421520166025 in words is "four hundred twenty-one billion, five hundred twenty million, one hundred sixty-six thousand, twenty-five".