66520664 has 32 divisors (see below), whose sum is σ = 147463200. Its totient is φ = 27525120.

The previous prime is 66520661. The next prime is 66520673. The reversal of 66520664 is 46602566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66520661) 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, 18857 + ... + 22104.

It is an arithmetic number, because the mean of its divisors is an integer number (4608225).

Almost surely, 2^66520664 is an apocalyptic number.

It is an amenable number.

66520664 is an abundant number, since it is smaller than the sum of its proper divisors (80942536).

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

66520664 is a wasteful number, since it uses less digits than its factorization.

66520664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41003 (or 40999 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 66520664 is about 8156.0201078712. The cubic root of 66520664 is about 405.1839107832.

The spelling of 66520664 in words is "sixty-six million, five hundred twenty thousand, six hundred sixty-four".