81607237144 has 16 divisors (see below), whose sum is σ = 153068200920. Its totient is φ = 40789050240.

The previous prime is 81607237133. The next prime is 81607237157. The reversal of 81607237144 is 44173270618.

It is a self number, because there is not a number n which added to its sum of digits gives 81607237144.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1797217 + ... + 1842064.

Almost surely, 2^81607237144 is an apocalyptic number.

It is an amenable number.

81607237144 is a deficient number, since it is larger than the sum of its proper divisors (71460963776).

81607237144 is a wasteful number, since it uses less digits than its factorization.

81607237144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3642090 (or 3642086 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 43.

The spelling of 81607237144 in words is "eighty-one billion, six hundred seven million, two hundred thirty-seven thousand, one hundred forty-four".