642668730840 has 48 divisors (see below), whose sum is σ = 2088673376400. Its totient is φ = 171378328128.

The previous prime is 642668730833. The next prime is 642668730857. The reversal of 642668730840 is 48037866246.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 892595100 + ... + 892595819.

It is an arithmetic number, because the mean of its divisors is an integer number (43514028675).

Almost surely, 2^642668730840 is an apocalyptic number.

642668730840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

642668730840 is an abundant number, since it is smaller than the sum of its proper divisors (1446004645560).

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

642668730840 is a wasteful number, since it uses less digits than its factorization.

642668730840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1785190936 (or 1785190929 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 54.

The spelling of 642668730840 in words is "six hundred forty-two billion, six hundred sixty-eight million, seven hundred thirty thousand, eight hundred forty".