80618921 has 2 divisors, whose sum is σ = 80618922. Its totient is φ = 80618920.

The previous prime is 80618917. The next prime is 80618929. The reversal of 80618921 is 12981608.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78074896 + 2544025 = 8836^2 + 1595^2 .

It is a cyclic number.

It is not a de Polignac number, because 80618921 - 2² = 80618917 is a prime.

It is not a weakly prime, because it can be changed into another prime (80618929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40309460 + 40309461.

It is an arithmetic number, because the mean of its divisors is an integer number (40309461).

Almost surely, 2^80618921 is an apocalyptic number.

It is an amenable number.

80618921 is a deficient number, since it is larger than the sum of its proper divisors (1).

80618921 is an equidigital number, since it uses as much as digits as its factorization.

80618921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 80618921 is about 8978.8039849414. The cubic root of 80618921 is about 431.9952720819.

The spelling of 80618921 in words is "eighty million, six hundred eighteen thousand, nine hundred twenty-one".