1640831864 has 24 divisors (see below), whose sum is σ = 3516717960. Its totient is φ = 703083744.

The previous prime is 1640831837. The next prime is 1640831867. The reversal of 1640831864 is 4681380461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640831867) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 300422 + ... + 305834.

It is an arithmetic number, because the mean of its divisors is an integer number (146529915).

Almost surely, 2^1640831864 is an apocalyptic number.

1640831864 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1640831864 is an abundant number, since it is smaller than the sum of its proper divisors (1875886096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640831864 is an frugal number, since it uses more digits than its factorization.

1640831864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10839 (or 5422 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 41.

The square root of 1640831864 is about 40507.1828692147. The cubic root of 1640831864 is about 1179.4730635887.

The spelling of 1640831864 in words is "one billion, six hundred forty million, eight hundred thirty-one thousand, eight hundred sixty-four".