80999979 has 16 divisors (see below), whose sum is σ = 110192640. Its totient is φ = 52909920.

The previous prime is 80999957. The next prime is 81000001. The reversal of 80999979 is 97999908.

It is an interprime number because it is at equal distance from previous prime (80999957) and next prime (81000001).

It is not a de Polignac number, because 80999979 - 2⁹ = 80999467 is a prime.

It is not an unprimeable number, because it can be changed into a prime (80999909) 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, 73974 + ... + 75060.

It is an arithmetic number, because the mean of its divisors is an integer number (6887040).

Almost surely, 2^80999979 is an apocalyptic number.

80999979 is a deficient number, since it is larger than the sum of its proper divisors (29192661).

80999979 is a wasteful number, since it uses less digits than its factorization.

80999979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1570.

The product of its (nonzero) digits is 3306744, while the sum is 60.

The square root of 80999979 is about 8999.9988333333. The cubic root of 80999979 is about 432.6748337006.

The spelling of 80999979 in words is "eighty million, nine hundred ninety-nine thousand, nine hundred seventy-nine".