640510311 has 48 divisors (see below), whose sum is σ = 1054176000. Its totient is φ = 344826720.

The previous prime is 640510291. The next prime is 640510337. The reversal of 640510311 is 113015046.

It is not a de Polignac number, because 640510311 - 2¹⁹ = 639986023 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640510391) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3538641 + ... + 3538821.

It is an arithmetic number, because the mean of its divisors is an integer number (21962000).

Almost surely, 2^640510311 is an apocalyptic number.

640510311 is a deficient number, since it is larger than the sum of its proper divisors (413665689).

640510311 is an equidigital number, since it uses as much as digits as its factorization.

640510311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 640510311 is about 25308.3051783402. The cubic root of 640510311 is about 862.0028634369.

Adding to 640510311 its reverse (113015046), we get a palindrome (753525357).

The spelling of 640510311 in words is "six hundred forty million, five hundred ten thousand, three hundred eleven".