64688599947 has 6 divisors (see below), whose sum is σ = 86252053972. Its totient is φ = 43125439612.

The previous prime is 64688599909. The next prime is 64688599957. The reversal of 64688599947 is 74999588646.

It is not a de Polignac number, because 64688599947 - 2⁸ = 64688599691 is a prime.

It is a super-2 number, since 2×64688599947² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64688599957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 367108 + ... + 513950.

Almost surely, 2^64688599947 is an apocalyptic number.

64688599947 is a deficient number, since it is larger than the sum of its proper divisors (21563454025).

64688599947 is an frugal number, since it uses more digits than its factorization.

64688599947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293689 (or 146846 counting only the distinct ones).

The product of its digits is 940584960, while the sum is 75.

Multiplying 64688599947 by its sum of digits (75), we get a square (4851644996025 = 2202645²).

The spelling of 64688599947 in words is "sixty-four billion, six hundred eighty-eight million, five hundred ninety-nine thousand, nine hundred forty-seven".