640183623 has 4 divisors (see below), whose sum is σ = 853578168. Its totient is φ = 426789080.

The previous prime is 640183619. The next prime is 640183627. The reversal of 640183623 is 326381046.

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

It is an interprime number because it is at equal distance from previous prime (640183619) and next prime (640183627).

It is a cyclic number.

It is not a de Polignac number, because 640183623 - 2² = 640183619 is a prime.

It is a super-2 number, since 2×640183623² = 819670142314812258, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640183627) 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, 106697268 + ... + 106697273.

It is an arithmetic number, because the mean of its divisors is an integer number (213394542).

Almost surely, 2^640183623 is an apocalyptic number.

640183623 is a deficient number, since it is larger than the sum of its proper divisors (213394545).

640183623 is a wasteful number, since it uses less digits than its factorization.

640183623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213394544.

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 640183623 is about 25301.8501892648. The cubic root of 640183623 is about 861.8562855821.

The spelling of 640183623 in words is "six hundred forty million, one hundred eighty-three thousand, six hundred twenty-three".