77897767 has 4 divisors (see below), whose sum is σ = 78654160. Its totient is φ = 77141376.

The previous prime is 77897749. The next prime is 77897779. The reversal of 77897767 is 76779877.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77897767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77897717) 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, 378042 + ... + 378247.

It is an arithmetic number, because the mean of its divisors is an integer number (19663540).

Almost surely, 2^77897767 is an apocalyptic number.

77897767 is a deficient number, since it is larger than the sum of its proper divisors (756393).

77897767 is a wasteful number, since it uses less digits than its factorization.

77897767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 756392.

The product of its digits is 7260624, while the sum is 58.

The square root of 77897767 is about 8825.9711646934. The cubic root of 77897767 is about 427.0791170194.

The spelling of 77897767 in words is "seventy-seven million, eight hundred ninety-seven thousand, seven hundred sixty-seven".