642497281858 has 16 divisors (see below), whose sum is σ = 974371646304. Its totient is φ = 317716725600.

The previous prime is 642497281849. The next prime is 642497281919. The reversal of 642497281858 is 858182794246.

It is a self number, because there is not a number n which added to its sum of digits gives 642497281858.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2369160 + ... + 2626387.

It is an arithmetic number, because the mean of its divisors is an integer number (60898227894).

Almost surely, 2^642497281858 is an apocalyptic number.

642497281858 is a deficient number, since it is larger than the sum of its proper divisors (331874364446).

642497281858 is a wasteful number, since it uses less digits than its factorization.

642497281858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4996257.

The product of its digits is 61931520, while the sum is 64.

The spelling of 642497281858 in words is "six hundred forty-two billion, four hundred ninety-seven million, two hundred eighty-one thousand, eight hundred fifty-eight".