66507620 has 12 divisors (see below), whose sum is σ = 139666044. Its totient is φ = 26603040.

The previous prime is 66507613. The next prime is 66507641. The reversal of 66507620 is 2670566.

It can be written as a sum of positive squares in 2 ways, for example, as 45914176 + 20593444 = 6776^2 + 4538^2 .

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1662671 + ... + 1662710.

It is an arithmetic number, because the mean of its divisors is an integer number (11638837).

Almost surely, 2^66507620 is an apocalyptic number.

It is an amenable number.

66507620 is an abundant number, since it is smaller than the sum of its proper divisors (73158424).

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

66507620 is a wasteful number, since it uses less digits than its factorization.

66507620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3325390 (or 3325388 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 66507620 is about 8155.2204139435. The cubic root of 66507620 is about 405.1574249560.

The spelling of 66507620 in words is "sixty-six million, five hundred seven thousand, six hundred twenty".