80921816 has 8 divisors (see below), whose sum is σ = 151728420. Its totient is φ = 40460904.

The previous prime is 80921809. The next prime is 80921851. The reversal of 80921816 is 61812908.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5057606 + ... + 5057621.

Almost surely, 2^80921816 is an apocalyptic number.

It is an amenable number.

80921816 is a deficient number, since it is larger than the sum of its proper divisors (70806604).

80921816 is a wasteful number, since it uses less digits than its factorization.

80921816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10115233 (or 10115229 counting only the distinct ones).

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

The square root of 80921816 is about 8995.6553958008. The cubic root of 80921816 is about 432.5356153637.

The spelling of 80921816 in words is "eighty million, nine hundred twenty-one thousand, eight hundred sixteen".