77971545 has 32 divisors (see below), whose sum is σ = 142007040. Its totient is φ = 40567680.

The previous prime is 77971511. The next prime is 77971577. The reversal of 77971545 is 54517977.

It is not a de Polignac number, because 77971545 - 2²⁶ = 10862681 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 77971545.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1509 + ... + 12578.

It is an arithmetic number, because the mean of its divisors is an integer number (4437720).

Almost surely, 2^77971545 is an apocalyptic number.

It is an amenable number.

77971545 is a deficient number, since it is larger than the sum of its proper divisors (64035495).

77971545 is a wasteful number, since it uses less digits than its factorization.

77971545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14142 (or 14136 counting only the distinct ones).

The product of its digits is 308700, while the sum is 45.

The square root of 77971545 is about 8830.1497722292. The cubic root of 77971545 is about 427.2139052253.

The spelling of 77971545 in words is "seventy-seven million, nine hundred seventy-one thousand, five hundred forty-five".