621645042 has 16 divisors (see below), whose sum is σ = 1252782432. Its totient is φ = 205632960.

The previous prime is 621645019. The next prime is 621645049. The reversal of 621645042 is 240546126.

It is not an unprimeable number, because it can be changed into a prime (621645049) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 394663 + ... + 396234.

It is an arithmetic number, because the mean of its divisors is an integer number (78298902).

Almost surely, 2^621645042 is an apocalyptic number.

621645042 is an abundant number, since it is smaller than the sum of its proper divisors (631137390).

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

621645042 is a wasteful number, since it uses less digits than its factorization.

621645042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791033.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 621645042 is about 24932.8105515604. The cubic root of 621645042 is about 853.4553884589.

The spelling of 621645042 in words is "six hundred twenty-one million, six hundred forty-five thousand, forty-two".