666525522 has 24 divisors (see below), whose sum is σ = 1443483504. Its totient is φ = 205084464.

The previous prime is 666525481. The next prime is 666525523. The reversal of 666525522 is 225525666.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (666525523) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 327648 + ... + 329675.

It is an arithmetic number, because the mean of its divisors is an integer number (60145146).

Almost surely, 2^666525522 is an apocalyptic number.

666525522 is an abundant number, since it is smaller than the sum of its proper divisors (776957982).

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

666525522 is a wasteful number, since it uses less digits than its factorization.

666525522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657354 (or 657341 counting only the distinct ones).

The product of its digits is 216000, while the sum is 39.

The square root of 666525522 is about 25817.1555753146. The cubic root of 666525522 is about 873.5188097732.

The spelling of 666525522 in words is "six hundred sixty-six million, five hundred twenty-five thousand, five hundred twenty-two".