77777764 has 6 divisors (see below), whose sum is σ = 136111094. Its totient is φ = 38888880.

The previous prime is 77777761. The next prime is 77777803. The reversal of 77777764 is 46777777.

It can be written as a sum of positive squares in only one way, i.e., 54641664 + 23136100 = 7392^2 + 4810^2 .

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (77777761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9722217 + ... + 9722224.

Almost surely, 2^77777764 is an apocalyptic number.

It is an amenable number.

77777764 is a deficient number, since it is larger than the sum of its proper divisors (58333330).

77777764 is a wasteful number, since it uses less digits than its factorization.

77777764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19444445 (or 19444443 counting only the distinct ones).

The product of its digits is 2823576, while the sum is 52.

The square root of 77777764 is about 8819.1702557554. The cubic root of 77777764 is about 426.8596964574.

The spelling of 77777764 in words is "seventy-seven million, seven hundred seventy-seven thousand, seven hundred sixty-four".