91724690 has 32 divisors (see below), whose sum is σ = 182424960. Its totient is φ = 33028864.

The previous prime is 91724681. The next prime is 91724747. The reversal of 91724690 is 9642719.

It is a super-2 number, since 2×91724690² = 16826837511192200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7820 + ... + 15639.

It is an arithmetic number, because the mean of its divisors is an integer number (5700780).

Almost surely, 2^91724690 is an apocalyptic number.

91724690 is the 7820-th pentagonal number.

91724690 is a deficient number, since it is larger than the sum of its proper divisors (90700270).

91724690 is a wasteful number, since it uses less digits than its factorization.

91724690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23506.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 91724690 is about 9577.3007679617. The cubic root of 91724690 is about 450.9849864636.

The spelling of 91724690 in words is "ninety-one million, seven hundred twenty-four thousand, six hundred ninety".