667788856 has 96 divisors (see below), whose sum is σ = 1516838400. Its totient is φ = 274518720.

The previous prime is 667788851. The next prime is 667788857. The reversal of 667788856 is 658887766.

It is a junction number, because it is equal to n+sod(n) for n = 667788794 and 667788803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667788851) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2175055 + ... + 2175361.

It is an arithmetic number, because the mean of its divisors is an integer number (15800400).

Almost surely, 2^667788856 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 667788856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (758419200).

667788856 is an abundant number, since it is smaller than the sum of its proper divisors (849049544).

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

667788856 is a wasteful number, since it uses less digits than its factorization.

667788856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537 (or 526 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 61.

The square root of 667788856 is about 25841.6109404967. The cubic root of 667788856 is about 874.0703513060.

The spelling of 667788856 in words is "six hundred sixty-seven million, seven hundred eighty-eight thousand, eight hundred fifty-six".