80981609 has 2 divisors, whose sum is σ = 80981610. Its totient is φ = 80981608.

The previous prime is 80981573. The next prime is 80981617. The reversal of 80981609 is 90618908.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61152400 + 19829209 = 7820^2 + 4453^2 .

It is a cyclic number.

It is not a de Polignac number, because 80981609 - 2²⁰ = 79933033 is a prime.

It is not a weakly prime, because it can be changed into another prime (80981669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40490804 + 40490805.

It is an arithmetic number, because the mean of its divisors is an integer number (40490805).

Almost surely, 2^80981609 is an apocalyptic number.

It is an amenable number.

80981609 is a deficient number, since it is larger than the sum of its proper divisors (1).

80981609 is an equidigital number, since it uses as much as digits as its factorization.

80981609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 41.

The square root of 80981609 is about 8998.9782197758. The cubic root of 80981609 is about 432.6421224261.

The spelling of 80981609 in words is "eighty million, nine hundred eighty-one thousand, six hundred nine".