82801621 has 6 divisors (see below), whose sum is σ = 96320310. Its totient is φ = 70972776.

The previous prime is 82801613. The next prime is 82801627. The reversal of 82801621 is 12610828.

It can be written as a sum of positive squares in only one way, i.e., 70795396 + 12006225 = 8414^2 + 3465^2 .

It is not a de Polignac number, because 82801621 - 2³ = 82801613 is a prime.

It is a super-2 number, since 2×82801621² = 13712216880455282, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 82801621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82801627) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 844866 + ... + 844963.

It is an arithmetic number, because the mean of its divisors is an integer number (16053385).

Almost surely, 2^82801621 is an apocalyptic number.

It is an amenable number.

82801621 is a deficient number, since it is larger than the sum of its proper divisors (13518689).

82801621 is a wasteful number, since it uses less digits than its factorization.

82801621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1689843 (or 1689836 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 82801621 is about 9099.5396037382. The cubic root of 82801621 is about 435.8592625045.

The spelling of 82801621 in words is "eighty-two million, eight hundred one thousand, six hundred twenty-one".