77971156 has 6 divisors (see below), whose sum is σ = 136449530. Its totient is φ = 38985576.

The previous prime is 77971139. The next prime is 77971177. The reversal of 77971156 is 65117977.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 47831056 + 30140100 = 6916^2 + 5490^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9746391 + ... + 9746398.

Almost surely, 2^77971156 is an apocalyptic number.

It is an amenable number.

77971156 is a deficient number, since it is larger than the sum of its proper divisors (58478374).

77971156 is a wasteful number, since it uses less digits than its factorization.

77971156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19492793 (or 19492791 counting only the distinct ones).

The product of its digits is 92610, while the sum is 43.

The square root of 77971156 is about 8830.1277453953. The cubic root of 77971156 is about 427.2131947675.

The spelling of 77971156 in words is "seventy-seven million, nine hundred seventy-one thousand, one hundred fifty-six".