642377856 has 64 divisors (see below), whose sum is σ = 1780528320. Its totient is φ = 204813312.

The previous prime is 642377819. The next prime is 642377893. The reversal of 642377856 is 658773246.

It is an interprime number because it is at equal distance from previous prime (642377819) and next prime (642377893).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (48).

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 7 ways as a sum of consecutive naturals, for example, 27535 + ... + 45198.

It is an arithmetic number, because the mean of its divisors is an integer number (27820755).

Almost surely, 2^642377856 is an apocalyptic number.

It is an amenable number.

642377856 is an abundant number, since it is smaller than the sum of its proper divisors (1138150464).

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

642377856 is a wasteful number, since it uses less digits than its factorization.

642377856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72773 (or 72761 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 48.

The square root of 642377856 is about 25345.1742152229. The cubic root of 642377856 is about 862.8398351655.

The spelling of 642377856 in words is "six hundred forty-two million, three hundred seventy-seven thousand, eight hundred fifty-six".