80921915 has 16 divisors (see below), whose sum is σ = 100504800. Its totient is φ = 62506752.

The previous prime is 80921909. The next prime is 80921917. The reversal of 80921915 is 51912908.

It is a cyclic number.

It is not a de Polignac number, because 80921915 - 2⁶ = 80921851 is a prime.

It is not an unprimeable number, because it can be changed into a prime (80921917) 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, 17021 + ... + 21249.

It is an arithmetic number, because the mean of its divisors is an integer number (6281550).

Almost surely, 2^80921915 is an apocalyptic number.

80921915 is a deficient number, since it is larger than the sum of its proper divisors (19582885).

80921915 is a wasteful number, since it uses less digits than its factorization.

80921915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4366.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 80921915 is about 8995.6608984554. The cubic root of 80921915 is about 432.5357917521.

The spelling of 80921915 in words is "eighty million, nine hundred twenty-one thousand, nine hundred fifteen".