640452231 has 16 divisors (see below), whose sum is σ = 951697920. Its totient is φ = 425672280.

The previous prime is 640452229. The next prime is 640452233. The reversal of 640452231 is 132254046.

It is an interprime number because it is at equal distance from previous prime (640452229) and next prime (640452233).

It is not a de Polignac number, because 640452231 - 2¹ = 640452229 is a prime.

It is a super-2 number, since 2×640452231² = 820358120385754722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 640452195 and 640452204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640452233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26895 + ... + 44768.

It is an arithmetic number, because the mean of its divisors is an integer number (59481120).

Almost surely, 2^640452231 is an apocalyptic number.

640452231 is a deficient number, since it is larger than the sum of its proper divisors (311245689).

640452231 is a wasteful number, since it uses less digits than its factorization.

640452231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72003 (or 71997 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 640452231 is about 25307.1577029109. The cubic root of 640452231 is about 861.9768078378.

The spelling of 640452231 in words is "six hundred forty million, four hundred fifty-two thousand, two hundred thirty-one".