668782772 has 72 divisors (see below), whose sum is σ = 1398196800. Its totient is φ = 279770400.

The previous prime is 668782769. The next prime is 668782783. The reversal of 668782772 is 277287866.

It is a super-2 number, since 2×668782772² = 894540792248007968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5105147 + ... + 5105277.

It is an arithmetic number, because the mean of its divisors is an integer number (19419400).

Almost surely, 2^668782772 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 668782772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (699098400).

668782772 is an abundant number, since it is smaller than the sum of its proper divisors (729414028).

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

668782772 is a wasteful number, since it uses less digits than its factorization.

668782772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 201 counting only the distinct ones).

The product of its digits is 3161088, while the sum is 53.

The square root of 668782772 is about 25860.8347119732. The cubic root of 668782772 is about 874.5037826456.

The spelling of 668782772 in words is "six hundred sixty-eight million, seven hundred eighty-two thousand, seven hundred seventy-two".