66720606 has 16 divisors (see below), whose sum is σ = 136545024. Its totient is φ = 21722904.

The previous prime is 66720559. The next prime is 66720659. The reversal of 66720606 is 60602766.

It is a congruent number.

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, 129046 + ... + 129561.

It is an arithmetic number, because the mean of its divisors is an integer number (8534064).

Almost surely, 2^66720606 is an apocalyptic number.

66720606 is an abundant number, since it is smaller than the sum of its proper divisors (69824418).

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

66720606 is a wasteful number, since it uses less digits than its factorization.

66720606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258655.

The product of its (nonzero) digits is 18144, while the sum is 33.

The square root of 66720606 is about 8168.2682375152. The cubic root of 66720606 is about 405.5894601986.

The spelling of 66720606 in words is "sixty-six million, seven hundred twenty thousand, six hundred six".