668136231530 has 16 divisors (see below), whose sum is σ = 1202678797320. Its totient is φ = 267247030272.

The previous prime is 668136231509. The next prime is 668136231563. The reversal of 668136231530 is 35132631866.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 611387939569 + 56748291961 = 781913^2 + 238219^2 .

It is a super-2 number, since 2×668136231530² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 549239 + ... + 1279818.

Almost surely, 2^668136231530 is an apocalyptic number.

668136231530 is a deficient number, since it is larger than the sum of its proper divisors (534542565790).

668136231530 is a wasteful number, since it uses less digits than its factorization.

668136231530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1865593.

The product of its (nonzero) digits is 466560, while the sum is 44.

The spelling of 668136231530 in words is "six hundred sixty-eight billion, one hundred thirty-six million, two hundred thirty-one thousand, five hundred thirty".