64647445791 has 4 divisors (see below), whose sum is σ = 86196594392. Its totient is φ = 43098297192.

The previous prime is 64647445741. The next prime is 64647445813. The reversal of 64647445791 is 19754474646.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 64647445791 - 2⁶ = 64647445727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64647445711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10774574296 + ... + 10774574301.

It is an arithmetic number, because the mean of its divisors is an integer number (21549148598).

Almost surely, 2^64647445791 is an apocalyptic number.

64647445791 is a deficient number, since it is larger than the sum of its proper divisors (21549148601).

64647445791 is a wasteful number, since it uses less digits than its factorization.

64647445791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21549148600.

The product of its digits is 20321280, while the sum is 57.

The spelling of 64647445791 in words is "sixty-four billion, six hundred forty-seven million, four hundred forty-five thousand, seven hundred ninety-one".