668145136 has 20 divisors (see below), whose sum is σ = 1318957992. Its totient is φ = 327768896.

The previous prime is 668145133. The next prime is 668145151. The reversal of 668145136 is 631541866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668145131) 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, 393106 + ... + 394801.

Almost surely, 2^668145136 is an apocalyptic number.

It is an amenable number.

668145136 is a deficient number, since it is larger than the sum of its proper divisors (650812856).

668145136 is a wasteful number, since it uses less digits than its factorization.

668145136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787968 (or 787962 counting only the distinct ones).

The product of its digits is 103680, while the sum is 40.

The square root of 668145136 is about 25848.5035543646. The cubic root of 668145136 is about 874.2257689036.

The spelling of 668145136 in words is "six hundred sixty-eight million, one hundred forty-five thousand, one hundred thirty-six".