82839721 has 16 divisors (see below), whose sum is σ = 89486208. Its totient is φ = 76489600.

The previous prime is 82839703. The next prime is 82839787. The reversal of 82839721 is 12793828.

It is not a de Polignac number, because 82839721 - 2⁹ = 82839209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82839121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100491 + ... + 101311.

It is an arithmetic number, because the mean of its divisors is an integer number (5592888).

Almost surely, 2^82839721 is an apocalyptic number.

It is an amenable number.

82839721 is a deficient number, since it is larger than the sum of its proper divisors (6646487).

82839721 is a wasteful number, since it uses less digits than its factorization.

82839721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992.

The product of its digits is 48384, while the sum is 40.

The square root of 82839721 is about 9101.6328754790. The cubic root of 82839721 is about 435.9261037544.

The spelling of 82839721 in words is "eighty-two million, eight hundred thirty-nine thousand, seven hundred twenty-one".