621240408 has 64 divisors (see below), whose sum is σ = 1728604800. Its totient is φ = 206727840.

The previous prime is 621240353. The next prime is 621240413. The reversal of 621240408 is 804042126.

621240408 is a `hidden beast` number, since 6 + 212 + 40 + 408 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 145423 + ... + 149633.

It is an arithmetic number, because the mean of its divisors is an integer number (27009450).

Almost surely, 2^621240408 is an apocalyptic number.

It is an amenable number.

621240408 is an abundant number, since it is smaller than the sum of its proper divisors (1107364392).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

621240408 is a wasteful number, since it uses less digits than its factorization.

621240408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4909 (or 4899 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 621240408 is about 24924.6947423634. The cubic root of 621240408 is about 853.2701744976.

The spelling of 621240408 in words is "six hundred twenty-one million, two hundred forty thousand, four hundred eight".