168656990 has 16 divisors (see below), whose sum is σ = 304683552. Its totient is φ = 67218144.

The previous prime is 168656981. The next prime is 168656993. The reversal of 168656990 is 99656861.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168656993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27674 + ... + 33213.

It is an arithmetic number, because the mean of its divisors is an integer number (19042722).

Almost surely, 2^168656990 is an apocalyptic number.

168656990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

168656990 is a deficient number, since it is larger than the sum of its proper divisors (136026562).

168656990 is a wasteful number, since it uses less digits than its factorization.

168656990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61171.

The product of its (nonzero) digits is 699840, while the sum is 50.

The square root of 168656990 is about 12986.8006067699. The cubic root of 168656990 is about 552.5031796873.

The spelling of 168656990 in words is "one hundred sixty-eight million, six hundred fifty-six thousand, nine hundred ninety".