81172592 has 10 divisors (see below), whose sum is σ = 157271928. Its totient is φ = 40586288.

The previous prime is 81172571. The next prime is 81172621. The reversal of 81172592 is 29527118.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2536628 + ... + 2536659.

Almost surely, 2^81172592 is an apocalyptic number.

It is an amenable number.

81172592 is a deficient number, since it is larger than the sum of its proper divisors (76099336).

81172592 is a wasteful number, since it uses less digits than its factorization.

81172592 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5073295 (or 5073289 counting only the distinct ones).

The product of its digits is 10080, while the sum is 35.

The square root of 81172592 is about 9009.5833421974. The cubic root of 81172592 is about 432.9819626349.

The spelling of 81172592 in words is "eighty-one million, one hundred seventy-two thousand, five hundred ninety-two".