621681025 has 12 divisors (see below), whose sum is σ = 881011072. Its totient is φ = 426295440.

The previous prime is 621681023. The next prime is 621681031. The reversal of 621681025 is 520186126.

It is not a de Polignac number, because 621681025 - 2¹ = 621681023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621681023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1776057 + ... + 1776406.

Almost surely, 2^621681025 is an apocalyptic number.

It is an amenable number.

621681025 is a deficient number, since it is larger than the sum of its proper divisors (259330047).

621681025 is a wasteful number, since it uses less digits than its factorization.

621681025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3552480 (or 3552475 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 621681025 is about 24933.5321404730. The cubic root of 621681025 is about 853.4718551404.

The spelling of 621681025 in words is "six hundred twenty-one million, six hundred eighty-one thousand, twenty-five".