82721670 has 32 divisors (see below), whose sum is σ = 199415520. Its totient is φ = 21960960.

The previous prime is 82721663. The next prime is 82721689. The reversal of 82721670 is 7612728.

It is a congruent number.

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, 850 + ... + 12890.

It is an arithmetic number, because the mean of its divisors is an integer number (6231735).

Almost surely, 2^82721670 is an apocalyptic number.

82721670 is an abundant number, since it is smaller than the sum of its proper divisors (116693850).

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

82721670 is a wasteful number, since it uses less digits than its factorization.

82721670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12280.

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 82721670 is about 9095.1454084033. The cubic root of 82721670 is about 435.7189327002.

The spelling of 82721670 in words is "eighty-two million, seven hundred twenty-one thousand, six hundred seventy".