640293379 has 16 divisors (see below), whose sum is σ = 706543200. Its totient is φ = 575424000.

The previous prime is 640293377. The next prime is 640293413. The reversal of 640293379 is 973392046.

It is a cyclic number.

It is not a de Polignac number, because 640293379 - 2¹ = 640293377 is a prime.

It is a super-2 number, since 2×640293379² = 819951222382475282, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (640293377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 394189 + ... + 395809.

It is an arithmetic number, because the mean of its divisors is an integer number (44158950).

Almost surely, 2^640293379 is an apocalyptic number.

640293379 is a deficient number, since it is larger than the sum of its proper divisors (66249821).

640293379 is a wasteful number, since it uses less digits than its factorization.

640293379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022.

The product of its (nonzero) digits is 244944, while the sum is 43.

The square root of 640293379 is about 25304.0190286049. The cubic root of 640293379 is about 861.9055362917.

The spelling of 640293379 in words is "six hundred forty million, two hundred ninety-three thousand, three hundred seventy-nine".