66959920 has 40 divisors (see below), whose sum is σ = 156061440. Its totient is φ = 26718720.

The previous prime is 66959897. The next prime is 66959941. The reversal of 66959920 is 2995966.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

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, 44785 + ... + 46255.

It is an arithmetic number, because the mean of its divisors is an integer number (3901536).

Almost surely, 2^66959920 is an apocalyptic number.

It is an amenable number.

66959920 is an abundant number, since it is smaller than the sum of its proper divisors (89101520).

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

66959920 is a wasteful number, since it uses less digits than its factorization.

66959920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2053 (or 2047 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 46.

The square root of 66959920 is about 8182.9041299529. The cubic root of 66959920 is about 406.0738054083.

The spelling of 66959920 in words is "sixty-six million, nine hundred fifty-nine thousand, nine hundred twenty".