645986522 has 8 divisors (see below), whose sum is σ = 973001172. Its totient is φ = 321652800.

The previous prime is 645986521. The next prime is 645986527. The reversal of 645986522 is 225689546.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 606686161 + 39300361 = 24631^2 + 6269^2 .

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

It is not an unprimeable number, because it can be changed into a prime (645986521) 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, 669629 + ... + 670592.

Almost surely, 2^645986522 is an apocalyptic number.

645986522 is a deficient number, since it is larger than the sum of its proper divisors (327014650).

645986522 is a wasteful number, since it uses less digits than its factorization.

645986522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340464.

The product of its digits is 1036800, while the sum is 47.

The square root of 645986522 is about 25416.2649104860. The cubic root of 645986522 is about 864.4525351762.

The spelling of 645986522 in words is "six hundred forty-five million, nine hundred eighty-six thousand, five hundred twenty-two".