80865561491 has 16 divisors (see below), whose sum is σ = 95137012320. Its totient is φ = 67763416320.

The previous prime is 80865561487. The next prime is 80865561521. The reversal of 80865561491 is 19416556808.

It is a cyclic number.

It is not a de Polignac number, because 80865561491 - 2² = 80865561487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (80865561481) 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, 297410 + ... + 500183.

It is an arithmetic number, because the mean of its divisors is an integer number (5946063270).

Almost surely, 2^80865561491 is an apocalyptic number.

80865561491 is a deficient number, since it is larger than the sum of its proper divisors (14271450829).

80865561491 is a wasteful number, since it uses less digits than its factorization.

80865561491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798326.

The product of its (nonzero) digits is 2073600, while the sum is 53.

The spelling of 80865561491 in words is "eighty billion, eight hundred sixty-five million, five hundred sixty-one thousand, four hundred ninety-one".