80021816621 has 16 divisors (see below), whose sum is σ = 86411673600. Its totient is φ = 73864253808.

The previous prime is 80021816603. The next prime is 80021816627. The reversal of 80021816621 is 12661812008.

It is a cyclic number.

It is not a de Polignac number, because 80021816621 - 2²⁶ = 79954707757 is a prime.

It is a super-2 number, since 2×80021816621² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80021816627) 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, 1781 + ... + 400058.

It is an arithmetic number, because the mean of its divisors is an integer number (5400729600).

Almost surely, 2^80021816621 is an apocalyptic number.

It is an amenable number.

80021816621 is a deficient number, since it is larger than the sum of its proper divisors (6389856979).

80021816621 is a wasteful number, since it uses less digits than its factorization.

80021816621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402128.

The product of its (nonzero) digits is 9216, while the sum is 35.

The spelling of 80021816621 in words is "eighty billion, twenty-one million, eight hundred sixteen thousand, six hundred twenty-one".