861037638 has 32 divisors (see below), whose sum is σ = 1774725120. Its totient is φ = 278322240.

The previous prime is 861037613. The next prime is 861037651. The reversal of 861037638 is 836730168.

It is a self number, because there is not a number n which added to its sum of digits gives 861037638.

It is a congruent number.

It is an unprimeable number.

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, 30603 + ... + 51561.

It is an arithmetic number, because the mean of its divisors is an integer number (55460160).

Almost surely, 2^861037638 is an apocalyptic number.

861037638 is an abundant number, since it is smaller than the sum of its proper divisors (913687482).

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

861037638 is a wasteful number, since it uses less digits than its factorization.

861037638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21172.

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 861037638 is about 29343.4428450378. The cubic root of 861037638 is about 951.3508531276.

The spelling of 861037638 in words is "eight hundred sixty-one million, thirty-seven thousand, six hundred thirty-eight".