77643776 has 60 divisors (see below), whose sum is σ = 177728208. Its totient is φ = 33226752.

The previous prime is 77643763. The next prime is 77643799. The reversal of 77643776 is 67734677.

It is a happy number.

Its product of digits (1037232) is a multiple of the sum of its prime divisors (686).

It is a self number, because there is not a number n which added to its sum of digits gives 77643776.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114350 + ... + 115026.

Almost surely, 2^77643776 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77643776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88864104).

77643776 is an abundant number, since it is smaller than the sum of its proper divisors (100084432).

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

77643776 is an frugal number, since it uses more digits than its factorization.

77643776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712 (or 686 counting only the distinct ones).

The product of its digits is 1037232, while the sum is 47.

The square root of 77643776 is about 8811.5705751018. The cubic root of 77643776 is about 426.6144380514.

Subtracting from 77643776 its reverse (67734677), we obtain a palindrome (9909099).

The spelling of 77643776 in words is "seventy-seven million, six hundred forty-three thousand, seven hundred seventy-six".