668691874501 has 12 divisors (see below), whose sum is σ = 777887348448. Its totient is φ = 573148776312.

The previous prime is 668691874481. The next prime is 668691874507. The reversal of 668691874501 is 105478196866.

It is a happy number.

It is not a de Polignac number, because 668691874501 - 2¹⁹ = 668691350213 is a prime.

It is a super-2 number, since 2×668691874501² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 668691874501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668691874507) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 1845070 + ... + 2177536.

It is an arithmetic number, because the mean of its divisors is an integer number (64823945704).

Almost surely, 2^668691874501 is an apocalyptic number.

It is an amenable number.

668691874501 is a deficient number, since it is larger than the sum of its proper divisors (109195473947).

668691874501 is a wasteful number, since it uses less digits than its factorization.

668691874501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373528 (or 373521 counting only the distinct ones).

The product of its (nonzero) digits is 17418240, while the sum is 61.

The spelling of 668691874501 in words is "six hundred sixty-eight billion, six hundred ninety-one million, eight hundred seventy-four thousand, five hundred one".