642923031820 has 24 divisors (see below), whose sum is σ = 1352719915344. Its totient is φ = 256677489216.

The previous prime is 642923031763. The next prime is 642923031823. The reversal of 642923031820 is 28130329246.

It is not an unprimeable number, because it can be changed into a prime (642923031823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30721999 + ... + 30742918.

It is an arithmetic number, because the mean of its divisors is an integer number (56363329806).

Almost surely, 2^642923031820 is an apocalyptic number.

It is an amenable number.

642923031820 is an abundant number, since it is smaller than the sum of its proper divisors (709796883524).

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

642923031820 is a wasteful number, since it uses less digits than its factorization.

642923031820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61465449 (or 61465447 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The spelling of 642923031820 in words is "six hundred forty-two billion, nine hundred twenty-three million, thirty-one thousand, eight hundred twenty".