64646667785 has 16 divisors (see below), whose sum is σ = 88669468800. Its totient is φ = 44323552896.

The previous prime is 64646667727. The next prime is 64646667791. The reversal of 64646667785 is 58776664646.

It is not a de Polignac number, because 64646667785 - 2⁶ = 64646667721 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175301 + ... + 400029.

It is an arithmetic number, because the mean of its divisors is an integer number (5541841800).

Almost surely, 2^64646667785 is an apocalyptic number.

It is an amenable number.

64646667785 is a deficient number, since it is larger than the sum of its proper divisors (24022801015).

64646667785 is a wasteful number, since it uses less digits than its factorization.

64646667785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232960.

The product of its digits is 243855360, while the sum is 65.

The spelling of 64646667785 in words is "sixty-four billion, six hundred forty-six million, six hundred sixty-seven thousand, seven hundred eighty-five".