66868990 has 32 divisors (see below), whose sum is σ = 130901184. Its totient is φ = 24491520.

The previous prime is 66868943. The next prime is 66869021. The reversal of 66868990 is 9986866.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 975 + ... + 11605.

It is an arithmetic number, because the mean of its divisors is an integer number (4090662).

Almost surely, 2^66868990 is an apocalyptic number.

66868990 is a deficient number, since it is larger than the sum of its proper divisors (64032194).

66868990 is a wasteful number, since it uses less digits than its factorization.

66868990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10692.

The product of its (nonzero) digits is 1119744, while the sum is 52.

The square root of 66868990 is about 8177.3461465197. The cubic root of 66868990 is about 405.8899092415.

The spelling of 66868990 in words is "sixty-six million, eight hundred sixty-eight thousand, nine hundred ninety".