668195631 has 24 divisors (see below), whose sum is σ = 973116144. Its totient is φ = 441815040.

The previous prime is 668195621. The next prime is 668195653. The reversal of 668195631 is 136591866.

668195631 is a `hidden beast` number, since 6 + 6 + 8 + 1 + 9 + 5 + 631 = 666.

It is not a de Polignac number, because 668195631 - 2¹¹ = 668193583 is a prime.

It is a super-3 number, since 3×668195631³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668195621) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 709621 + ... + 710561.

It is an arithmetic number, because the mean of its divisors is an integer number (40546506).

Almost surely, 2^668195631 is an apocalyptic number.

668195631 is a deficient number, since it is larger than the sum of its proper divisors (304920513).

668195631 is a wasteful number, since it uses less digits than its factorization.

668195631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1511 (or 1508 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The square root of 668195631 is about 25849.4802849110. The cubic root of 668195631 is about 874.2477915230.

The spelling of 668195631 in words is "six hundred sixty-eight million, one hundred ninety-five thousand, six hundred thirty-one".