642694805379 has 48 divisors (see below), whose sum is σ = 1077918326784. Its totient is φ = 364679980800.

The previous prime is 642694805369. The next prime is 642694805381. The reversal of 642694805379 is 973508496246.

642694805379 is a `hidden beast` number, since 6 + 4 + 2 + 6 + 94 + 8 + 0 + 537 + 9 = 666.

642694805379 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 642694805379 - 2⁷ = 642694805251 is a prime.

It is a super-2 number, since 2×642694805379² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (642694805359) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 678219 + ... + 1321124.

It is an arithmetic number, because the mean of its divisors is an integer number (22456631808).

Almost surely, 2^642694805379 is an apocalyptic number.

642694805379 is a deficient number, since it is larger than the sum of its proper divisors (435223521405).

642694805379 is a wasteful number, since it uses less digits than its factorization.

642694805379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1999568 (or 1999565 counting only the distinct ones).

The product of its (nonzero) digits is 78382080, while the sum is 63.

The spelling of 642694805379 in words is "six hundred forty-two billion, six hundred ninety-four million, eight hundred five thousand, three hundred seventy-nine".