640164052623 has 8 divisors (see below), whose sum is σ = 853571041408. Its totient is φ = 426766549464.

The previous prime is 640164052543. The next prime is 640164052657. The reversal of 640164052623 is 326250461046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640164052623 - 2²⁵ = 640130498191 is a prime.

It is a super-2 number, since 2×640164052623² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640164052223) 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, 2212411 + ... + 2484972.

It is an arithmetic number, because the mean of its divisors is an integer number (106696380176).

Almost surely, 2^640164052623 is an apocalyptic number.

640164052623 is a deficient number, since it is larger than the sum of its proper divisors (213406988785).

640164052623 is a wasteful number, since it uses less digits than its factorization.

640164052623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4742813.

The product of its (nonzero) digits is 207360, while the sum is 39.

The spelling of 640164052623 in words is "six hundred forty billion, one hundred sixty-four million, fifty-two thousand, six hundred twenty-three".