77689889 has 4 divisors (see below), whose sum is σ = 78023556. Its totient is φ = 77356224.

The previous prime is 77689861. The next prime is 77689897. The reversal of 77689889 is 98898677.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20430400 + 57259489 = 4520^2 + 7567^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77689889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77689589) 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, 166484 + ... + 166949.

It is an arithmetic number, because the mean of its divisors is an integer number (19505889).

Almost surely, 2^77689889 is an apocalyptic number.

It is an amenable number.

77689889 is a deficient number, since it is larger than the sum of its proper divisors (333667).

77689889 is a wasteful number, since it uses less digits than its factorization.

77689889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333666.

The product of its digits is 12192768, while the sum is 62.

The square root of 77689889 is about 8814.1868031033. The cubic root of 77689889 is about 426.6988774375.

The spelling of 77689889 in words is "seventy-seven million, six hundred eighty-nine thousand, eight hundred eighty-nine".