19640936068 has 12 divisors (see below), whose sum is σ = 37015610380. Its totient is φ = 9065047392.

The previous prime is 19640936041. The next prime is 19640936071. The reversal of 19640936068 is 86063904691.

It can be written as a sum of positive squares in 2 ways, for example, as 11351197764 + 8289738304 = 106542^2 + 91048^2 .

It is a Harshad number since it is a multiple of its sum of digits (52), and also a Moran number because the ratio is a prime number: 377710309 = 19640936068 / (1 + 9 + 6 + 4 + 0 + 9 + 3 + 6 + 0 + 6 + 8).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188855103 + ... + 188855206.

Almost surely, 2^19640936068 is an apocalyptic number.

It is an amenable number.

19640936068 is a deficient number, since it is larger than the sum of its proper divisors (17374674312).

19640936068 is a wasteful number, since it uses less digits than its factorization.

19640936068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377710326 (or 377710324 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 52.

The spelling of 19640936068 in words is "nineteen billion, six hundred forty million, nine hundred thirty-six thousand, sixty-eight".