66890064 has 40 divisors (see below), whose sum is σ = 178377472. Its totient is φ = 21576960.

The previous prime is 66890063. The next prime is 66890101. The reversal of 66890064 is 46009866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66890063) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20989 + ... + 23964.

Almost surely, 2^66890064 is an apocalyptic number.

It is an amenable number.

66890064 is an abundant number, since it is smaller than the sum of its proper divisors (111487408).

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

66890064 is a wasteful number, since it uses less digits than its factorization.

66890064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44995 (or 44989 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 66890064 is about 8178.6346048714. The cubic root of 66890064 is about 405.9325439791.

The spelling of 66890064 in words is "sixty-six million, eight hundred ninety thousand, sixty-four".