77367721 has 4 divisors (see below), whose sum is σ = 77410944. Its totient is φ = 77324500.

The previous prime is 77367713. The next prime is 77367769. The reversal of 77367721 is 12776377.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 77367721 - 2³ = 77367713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77367701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18805 + ... + 22546.

It is an arithmetic number, because the mean of its divisors is an integer number (19352736).

Almost surely, 2^77367721 is an apocalyptic number.

It is an amenable number.

77367721 is a deficient number, since it is larger than the sum of its proper divisors (43223).

77367721 is a wasteful number, since it uses less digits than its factorization.

77367721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43222.

The product of its digits is 86436, while the sum is 40.

The square root of 77367721 is about 8795.8922799225. The cubic root of 77367721 is about 426.1082420912.

The spelling of 77367721 in words is "seventy-seven million, three hundred sixty-seven thousand, seven hundred twenty-one".