668861244 has 36 divisors (see below), whose sum is σ = 1691652144. Its totient is φ = 222832512.

The previous prime is 668861213. The next prime is 668861257. The reversal of 668861244 is 442168866.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 668861244.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 83169 + ... + 90855.

Almost surely, 2^668861244 is an apocalyptic number.

It is an amenable number.

668861244 is an abundant number, since it is smaller than the sum of its proper divisors (1022790900).

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

668861244 is a wasteful number, since it uses less digits than its factorization.

668861244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10114 (or 10109 counting only the distinct ones).

The product of its digits is 442368, while the sum is 45.

The square root of 668861244 is about 25862.3518652113. The cubic root of 668861244 is about 874.5379847711.

The spelling of 668861244 in words is "six hundred sixty-eight million, eight hundred sixty-one thousand, two hundred forty-four".