83131640 has 32 divisors (see below), whose sum is σ = 187360560. Its totient is φ = 33196800.

The previous prime is 83131639. The next prime is 83131651. The reversal of 83131640 is 4613138.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29075 + ... + 31805.

Almost surely, 2^83131640 is an apocalyptic number.

It is an amenable number.

83131640 is an abundant number, since it is smaller than the sum of its proper divisors (104228920).

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

83131640 is a wasteful number, since it uses less digits than its factorization.

83131640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3503 (or 3499 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 83131640 is about 9117.6554003757. The cubic root of 83131640 is about 436.4375569741.

Adding to 83131640 its reverse (4613138), we get a palindrome (87744778).

The spelling of 83131640 in words is "eighty-three million, one hundred thirty-one thousand, six hundred forty".