664536522 has 32 divisors (see below), whose sum is σ = 1477486080. Its totient is φ = 197876160.

The previous prime is 664536497. The next prime is 664536527. The reversal of 664536522 is 225635466.

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 (664536527) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 134997 + ... + 139832.

It is an arithmetic number, because the mean of its divisors is an integer number (46171440).

Almost surely, 2^664536522 is an apocalyptic number.

664536522 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

664536522 is an abundant number, since it is smaller than the sum of its proper divisors (812949558).

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

664536522 is a wasteful number, since it uses less digits than its factorization.

664536522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274878.

The product of its digits is 259200, while the sum is 39.

The square root of 664536522 is about 25778.6058971388. The cubic root of 664536522 is about 872.6490456181.

The spelling of 664536522 in words is "six hundred sixty-four million, five hundred thirty-six thousand, five hundred twenty-two".