79987400491 has 4 divisors (see below), whose sum is σ = 80072403984. Its totient is φ = 79902397000.

The previous prime is 79987400447. The next prime is 79987400501. The reversal of 79987400491 is 19400478997.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 79987400491 - 2¹¹ = 79987398443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79987400431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42500335 + ... + 42502216.

It is an arithmetic number, because the mean of its divisors is an integer number (20018100996).

Almost surely, 2^79987400491 is an apocalyptic number.

79987400491 is a deficient number, since it is larger than the sum of its proper divisors (85003493).

79987400491 is an equidigital number, since it uses as much as digits as its factorization.

79987400491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85003492.

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 79987400491 in words is "seventy-nine billion, nine hundred eighty-seven million, four hundred thousand, four hundred ninety-one".