668742012 has 36 divisors (see below), whose sum is σ = 1779403080. Its totient is φ = 211181472.

The previous prime is 668742007. The next prime is 668742029. The reversal of 668742012 is 210247866.

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

It is a super-2 number, since 2×668742012² = 894431757227616288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 488163 + ... + 489530.

Almost surely, 2^668742012 is an apocalyptic number.

It is an amenable number.

668742012 is an abundant number, since it is smaller than the sum of its proper divisors (1110661068).

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

668742012 is a wasteful number, since it uses less digits than its factorization.

668742012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977722 (or 977717 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 668742012 is about 25860.0466356888. The cubic root of 668742012 is about 874.4860162896.

Adding to 668742012 its reverse (210247866), we get a palindrome (878989878).

It can be divided in two parts, 66874 and 2012, that added together give a palindrome (68886).

The spelling of 668742012 in words is "six hundred sixty-eight million, seven hundred forty-two thousand, twelve".