80561687 has 4 divisors (see below), whose sum is σ = 80579640. Its totient is φ = 80543736.

The previous prime is 80561669. The next prime is 80561707. The reversal of 80561687 is 78616508.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 80561687 - 2¹⁰ = 80560663 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80566687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4364 + ... + 13422.

It is an arithmetic number, because the mean of its divisors is an integer number (20144910).

Almost surely, 2^80561687 is an apocalyptic number.

80561687 is a deficient number, since it is larger than the sum of its proper divisors (17953).

80561687 is an equidigital number, since it uses as much as digits as its factorization.

80561687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17952.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 80561687 is about 8975.6162462530. The cubic root of 80561687 is about 431.8930187052.

The spelling of 80561687 in words is "eighty million, five hundred sixty-one thousand, six hundred eighty-seven".