645744522 has 8 divisors (see below), whose sum is σ = 1291489056. Its totient is φ = 215248172.

The previous prime is 645744521. The next prime is 645744529. The reversal of 645744522 is 225447546.

It is a sphenic number, since it is the product of 3 distinct primes.

645744522 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (645744521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53812038 + ... + 53812049.

It is an arithmetic number, because the mean of its divisors is an integer number (161436132).

Almost surely, 2^645744522 is an apocalyptic number.

645744522 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

645744522 is a wasteful number, since it uses less digits than its factorization.

645744522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107624092.

The product of its digits is 268800, while the sum is 39.

The square root of 645744522 is about 25411.5037335456. The cubic root of 645744522 is about 864.3445743880.

It can be divided in two parts, 64574 and 4522, that added together give a palindrome (69096).

The spelling of 645744522 in words is "six hundred forty-five million, seven hundred forty-four thousand, five hundred twenty-two".