64397772136 has 32 divisors (see below), whose sum is σ = 124112148840. Its totient is φ = 31302643968.

The previous prime is 64397772133. The next prime is 64397772181. The reversal of 64397772136 is 63127779346.

64397772136 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 62505000100 + 1892772036 = 250010^2 + 43506^2 .

It is a Smith number, since the sum of its digits (55) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (64397772133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269370 + ... + 448726.

Almost surely, 2^64397772136 is an apocalyptic number.

It is an amenable number.

64397772136 is a deficient number, since it is larger than the sum of its proper divisors (59714376704).

64397772136 is a wasteful number, since it uses less digits than its factorization.

64397772136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180613 (or 180609 counting only the distinct ones).

The product of its digits is 8001504, while the sum is 55.

The spelling of 64397772136 in words is "sixty-four billion, three hundred ninety-seven million, seven hundred seventy-two thousand, one hundred thirty-six".