66722790 has 32 divisors (see below), whose sum is σ = 169555680. Its totient is φ = 16745984.

The previous prime is 66722783. The next prime is 66722809. The reversal of 66722790 is 9722766.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64905 + ... + 65924.

It is an arithmetic number, because the mean of its divisors is an integer number (5298615).

Almost surely, 2^66722790 is an apocalyptic number.

66722790 is an abundant number, since it is smaller than the sum of its proper divisors (102832890).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66722790 is a wasteful number, since it uses less digits than its factorization.

66722790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130856.

The product of its (nonzero) digits is 63504, while the sum is 39.

The square root of 66722790 is about 8168.4019244893. The cubic root of 66722790 is about 405.5938856067.

The spelling of 66722790 in words is "sixty-six million, seven hundred twenty-two thousand, seven hundred ninety".