77128216 has 32 divisors (see below), whose sum is σ = 161617680. Its totient is φ = 34201600.

The previous prime is 77128199. The next prime is 77128231. The reversal of 77128216 is 61282177.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7081 + ... + 14296.

Almost surely, 2^77128216 is an apocalyptic number.

It is an amenable number.

77128216 is an abundant number, since it is smaller than the sum of its proper divisors (84489464).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77128216 is a wasteful number, since it uses less digits than its factorization.

77128216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21435 (or 21431 counting only the distinct ones).

The product of its digits is 9408, while the sum is 34.

The square root of 77128216 is about 8782.2671332635. The cubic root of 77128216 is about 425.6680906331.

The spelling of 77128216 in words is "seventy-seven million, one hundred twenty-eight thousand, two hundred sixteen".