77981375 has 8 divisors (see below), whose sum is σ = 97320912. Its totient is φ = 62385000.

The previous prime is 77981369. The next prime is 77981389. The reversal of 77981375 is 57318977.

It is not a de Polignac number, because 77981375 - 2¹² = 77977279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 311801 + ... + 312050.

It is an arithmetic number, because the mean of its divisors is an integer number (12165114).

Almost surely, 2^77981375 is an apocalyptic number.

77981375 is a deficient number, since it is larger than the sum of its proper divisors (19339537).

77981375 is an equidigital number, since it uses as much as digits as its factorization.

77981375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 623866 (or 623856 counting only the distinct ones).

The product of its digits is 370440, while the sum is 47.

The square root of 77981375 is about 8830.7063703874. The cubic root of 77981375 is about 427.2318576558.

The spelling of 77981375 in words is "seventy-seven million, nine hundred eighty-one thousand, three hundred seventy-five".