81501708 has 24 divisors (see below), whose sum is σ = 190935360. Its totient is φ = 27058000.

The previous prime is 81501701. The next prime is 81501709. The reversal of 81501708 is 80710518.

It is not an unprimeable number, because it can be changed into a prime (81501701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10518 + ... + 16541.

It is an arithmetic number, because the mean of its divisors is an integer number (7955640).

Almost surely, 2^81501708 is an apocalyptic number.

It is an amenable number.

81501708 is an abundant number, since it is smaller than the sum of its proper divisors (109433652).

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

81501708 is a wasteful number, since it uses less digits than its factorization.

81501708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27317 (or 27315 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 30.

The square root of 81501708 is about 9027.8296395092. The cubic root of 81501708 is about 433.5663517300.

The spelling of 81501708 in words is "eighty-one million, five hundred one thousand, seven hundred eight".