668881079 has 12 divisors (see below), whose sum is σ = 709668288. Its totient is φ = 629769600.

The previous prime is 668881069. The next prime is 668881091. The reversal of 668881079 is 970188866.

It is a de Polignac number, because none of the positive numbers 2^k-668881079 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 668881079.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668881019) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34559 + ... + 50319.

It is an arithmetic number, because the mean of its divisors is an integer number (59139024).

Almost surely, 2^668881079 is an apocalyptic number.

668881079 is a deficient number, since it is larger than the sum of its proper divisors (40787209).

668881079 is a wasteful number, since it uses less digits than its factorization.

668881079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15866 (or 15829 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 53.

The square root of 668881079 is about 25862.7353348404. The cubic root of 668881079 is about 874.5466294587.

The spelling of 668881079 in words is "six hundred sixty-eight million, eight hundred eighty-one thousand, seventy-nine".