80972991 has 24 divisors (see below), whose sum is σ = 130712400. Its totient is φ = 47875200.

The previous prime is 80972953. The next prime is 80972993. The reversal of 80972991 is 19927908.

It is not a de Polignac number, because 80972991 - 2¹⁹ = 80448703 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80972993) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5916 + ... + 14033.

It is an arithmetic number, because the mean of its divisors is an integer number (5446350).

Almost surely, 2^80972991 is an apocalyptic number.

80972991 is a deficient number, since it is larger than the sum of its proper divisors (49739409).

80972991 is a wasteful number, since it uses less digits than its factorization.

80972991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20007 (or 20004 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The square root of 80972991 is about 8998.4993748958. The cubic root of 80972991 is about 432.6267747353.

The spelling of 80972991 in words is "eighty million, nine hundred seventy-two thousand, nine hundred ninety-one".