66706820 has 24 divisors (see below), whose sum is σ = 140241024. Its totient is φ = 26652896.

The previous prime is 66706811. The next prime is 66706847. The reversal of 66706820 is 2860766.

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, 28619 + ... + 30861.

It is an arithmetic number, because the mean of its divisors is an integer number (5843376).

Almost surely, 2^66706820 is an apocalyptic number.

It is an amenable number.

66706820 is an abundant number, since it is smaller than the sum of its proper divisors (73534204).

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

66706820 is a wasteful number, since it uses less digits than its factorization.

66706820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3739 (or 3737 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 66706820 is about 8167.4243185964. The cubic root of 66706820 is about 405.5615235946.

The spelling of 66706820 in words is "sixty-six million, seven hundred six thousand, eight hundred twenty".