642064061620 has 12 divisors (see below), whose sum is σ = 1348334529444. Its totient is φ = 256825624640.

The previous prime is 642064061603. The next prime is 642064061627. The reversal of 642064061620 is 26160460246.

It can be written as a sum of positive squares in 2 ways, for example, as 69230029456 + 572834032164 = 263116^2 + 756858^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 642064061620.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642064061627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16051601521 + ... + 16051601560.

It is an arithmetic number, because the mean of its divisors is an integer number (112361210787).

Almost surely, 2^642064061620 is an apocalyptic number.

It is an amenable number.

642064061620 is an abundant number, since it is smaller than the sum of its proper divisors (706270467824).

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

642064061620 is a wasteful number, since it uses less digits than its factorization.

642064061620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32103203090 (or 32103203088 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 37.

The spelling of 642064061620 in words is "six hundred forty-two billion, sixty-four million, sixty-one thousand, six hundred twenty".