764216778 has 16 divisors (see below), whose sum is σ = 1646005536. Its totient is φ = 235143600.

The previous prime is 764216771. The next prime is 764216797. The reversal of 764216778 is 877612467.

It is not an unprimeable number, because it can be changed into a prime (764216771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4898748 + ... + 4898903.

It is an arithmetic number, because the mean of its divisors is an integer number (102875346).

Almost surely, 2^764216778 is an apocalyptic number.

764216778 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

764216778 is an abundant number, since it is smaller than the sum of its proper divisors (881788758).

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

764216778 is a wasteful number, since it uses less digits than its factorization.

764216778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9797669.

The product of its digits is 790272, while the sum is 48.

The square root of 764216778 is about 27644.4710204410. The cubic root of 764216778 is about 914.2652000303.

The spelling of 764216778 in words is "seven hundred sixty-four million, two hundred sixteen thousand, seven hundred seventy-eight".