668388837 has 4 divisors (see below), whose sum is σ = 891185120. Its totient is φ = 445592556.

The previous prime is 668388827. The next prime is 668388899. The reversal of 668388837 is 738883866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 668388837 - 2¹⁶ = 668323301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668388827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111398137 + ... + 111398142.

It is an arithmetic number, because the mean of its divisors is an integer number (222796280).

Almost surely, 2^668388837 is an apocalyptic number.

It is an amenable number.

668388837 is a deficient number, since it is larger than the sum of its proper divisors (222796283).

668388837 is a wasteful number, since it uses less digits than its factorization.

668388837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222796282.

The product of its digits is 9289728, while the sum is 57.

The square root of 668388837 is about 25853.2171499023. The cubic root of 668388837 is about 874.3320451127.

The spelling of 668388837 in words is "six hundred sixty-eight million, three hundred eighty-eight thousand, eight hundred thirty-seven".