82313721 has 24 divisors (see below), whose sum is σ = 137918144. Its totient is φ = 46332000.

The previous prime is 82313683. The next prime is 82313723. The reversal of 82313721 is 12731328.

It is not a de Polignac number, because 82313721 - 2⁶ = 82313657 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (82313723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5530 + ... + 13971.

Almost surely, 2^82313721 is an apocalyptic number.

It is an amenable number.

82313721 is a deficient number, since it is larger than the sum of its proper divisors (55604423).

82313721 is a wasteful number, since it uses less digits than its factorization.

82313721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19581 (or 19578 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 82313721 is about 9072.6909459101. The cubic root of 82313721 is about 435.0014902842.

The spelling of 82313721 in words is "eighty-two million, three hundred thirteen thousand, seven hundred twenty-one".