668288290 has 16 divisors (see below), whose sum is σ = 1215321912. Its totient is φ = 264559104.

The previous prime is 668288279. The next prime is 668288293. The reversal of 668288290 is 92882866.

It can be written as a sum of positive squares in 4 ways, for example, as 477378801 + 190909489 = 21849^2 + 13817^2 .

It is a super-2 number, since 2×668288290² = 893218477102248200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668288293) 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, 343509 + ... + 345448.

Almost surely, 2^668288290 is an apocalyptic number.

668288290 is a deficient number, since it is larger than the sum of its proper divisors (547033622).

668288290 is a wasteful number, since it uses less digits than its factorization.

668288290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689061.

The product of its (nonzero) digits is 663552, while the sum is 49.

The square root of 668288290 is about 25851.2725025288. The cubic root of 668288290 is about 874.2882004383.

The spelling of 668288290 in words is "six hundred sixty-eight million, two hundred eighty-eight thousand, two hundred ninety".