77156891 has 16 divisors (see below), whose sum is σ = 93135360. Its totient is φ = 62614728.

The previous prime is 77156869. The next prime is 77156899. The reversal of 77156891 is 19865177.

It is not a de Polignac number, because 77156891 - 2²² = 72962587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77156899) 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, 47210 + ... + 48816.

It is an arithmetic number, because the mean of its divisors is an integer number (5820960).

Almost surely, 2^77156891 is an apocalyptic number.

77156891 is a deficient number, since it is larger than the sum of its proper divisors (15978469).

77156891 is an equidigital number, since it uses as much as digits as its factorization.

77156891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1671 (or 1633 counting only the distinct ones).

The product of its digits is 105840, while the sum is 44.

The square root of 77156891 is about 8783.8995326677. The cubic root of 77156891 is about 425.7208362247.

The spelling of 77156891 in words is "seventy-seven million, one hundred fifty-six thousand, eight hundred ninety-one".