668164451 has 4 divisors (see below), whose sum is σ = 668468592. Its totient is φ = 667860312.

The previous prime is 668164429. The next prime is 668164477. The reversal of 668164451 is 154461866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 668164451 - 2²² = 663970147 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 668164399 and 668164408.

It is not an unprimeable number, because it can be changed into a prime (668164411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148751 + ... + 153176.

It is an arithmetic number, because the mean of its divisors is an integer number (167117148).

Almost surely, 2^668164451 is an apocalyptic number.

668164451 is a deficient number, since it is larger than the sum of its proper divisors (304141).

668164451 is a wasteful number, since it uses less digits than its factorization.

668164451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304140.

The product of its digits is 138240, while the sum is 41.

The square root of 668164451 is about 25848.8771709720. The cubic root of 668164451 is about 874.2341929755.

The spelling of 668164451 in words is "six hundred sixty-eight million, one hundred sixty-four thousand, four hundred fifty-one".