80981805 has 16 divisors (see below), whose sum is σ = 129801600. Its totient is φ = 43113408.

The previous prime is 80981801. The next prime is 80981809. The reversal of 80981805 is 50818908.

It is an interprime number because it is at equal distance from previous prime (80981801) and next prime (80981809).

It is not a de Polignac number, because 80981805 - 2² = 80981801 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80981801) 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, 4479 + ... + 13491.

It is an arithmetic number, because the mean of its divisors is an integer number (8112600).

Almost surely, 2^80981805 is an apocalyptic number.

It is an amenable number.

80981805 is a deficient number, since it is larger than the sum of its proper divisors (48819795).

80981805 is a wasteful number, since it uses less digits than its factorization.

80981805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9620.

The product of its (nonzero) digits is 23040, while the sum is 39.

The square root of 80981805 is about 8998.9891098945. The cubic root of 80981805 is about 432.6424714674.

The spelling of 80981805 in words is "eighty million, nine hundred eighty-one thousand, eight hundred five".