668194190 has 16 divisors (see below), whose sum is σ = 1207744560. Its totient is φ = 266167680.

The previous prime is 668194187. The next prime is 668194201. The reversal of 668194190 is 91491866.

It is a super-2 number, since 2×668194190² = 892966951099512200, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136220 + ... + 141039.

It is an arithmetic number, because the mean of its divisors is an integer number (75484035).

Almost surely, 2^668194190 is an apocalyptic number.

668194190 is a deficient number, since it is larger than the sum of its proper divisors (539550370).

668194190 is a wasteful number, since it uses less digits than its factorization.

668194190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277507.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 668194190 is about 25849.4524119951. The cubic root of 668194190 is about 874.2471630684.

The spelling of 668194190 in words is "six hundred sixty-eight million, one hundred ninety-four thousand, one hundred ninety".