64220640464 has 20 divisors (see below), whose sum is σ = 124572369120. Its totient is φ = 32072932320.

The previous prime is 64220640437. The next prime is 64220640467. The reversal of 64220640464 is 46404602246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64220640467) 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, 2322572 + ... + 2350059.

It is an arithmetic number, because the mean of its divisors is an integer number (6228618456).

Almost surely, 2^64220640464 is an apocalyptic number.

It is an amenable number.

64220640464 is a deficient number, since it is larger than the sum of its proper divisors (60351728656).

64220640464 is a wasteful number, since it uses less digits than its factorization.

64220640464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4673498 (or 4673492 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 38.

The spelling of 64220640464 in words is "sixty-four billion, two hundred twenty million, six hundred forty thousand, four hundred sixty-four".