668722 has 8 divisors (see below), whose sum is σ = 1008000. Its totient is φ = 332724.

The previous prime is 668719. The next prime is 668737. The reversal of 668722 is 227866.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×668722² = 894378226568, which contains 22 as substring.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222 + ... + 1177.

It is an arithmetic number, because the mean of its divisors is an integer number (126000).

2⁶⁶⁸⁷²² is an apocalyptic number.

668722 is a deficient number, since it is larger than the sum of its proper divisors (339278).

668722 is a wasteful number, since it uses less digits than its factorization.

668722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1640.

The product of its digits is 8064, while the sum is 31.

The square root of 668722 is about 817.7542418111. The cubic root of 668722 is about 87.4477293250.

The spelling of 668722 in words is "six hundred sixty-eight thousand, seven hundred twenty-two".