668388427 has 32 divisors (see below), whose sum is σ = 807403520. Its totient is φ = 541326240.

The previous prime is 668388421. The next prime is 668388443. The reversal of 668388427 is 724883866.

It is not a de Polignac number, because 668388427 - 2³ = 668388419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (668388421) 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 31 ways as a sum of consecutive naturals, for example, 2177008 + ... + 2177314.

It is an arithmetic number, because the mean of its divisors is an integer number (25231360).

Almost surely, 2^668388427 is an apocalyptic number.

668388427 is a deficient number, since it is larger than the sum of its proper divisors (139015093).

668388427 is a wasteful number, since it uses less digits than its factorization.

668388427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551.

The product of its digits is 3096576, while the sum is 52.

The square root of 668388427 is about 25853.2092205204. The cubic root of 668388427 is about 874.3318663364.

The spelling of 668388427 in words is "six hundred sixty-eight million, three hundred eighty-eight thousand, four hundred twenty-seven".