645611522 has 4 divisors (see below), whose sum is σ = 968417286. Its totient is φ = 322805760.

The previous prime is 645611513. The next prime is 645611569. The reversal of 645611522 is 225116546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 640140601 + 5470921 = 25301^2 + 2339^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161402879 + ... + 161402882.

Almost surely, 2^645611522 is an apocalyptic number.

645611522 is a deficient number, since it is larger than the sum of its proper divisors (322805764).

645611522 is a wasteful number, since it uses less digits than its factorization.

645611522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322805763.

The product of its digits is 14400, while the sum is 32.

The square root of 645611522 is about 25408.8866737604. The cubic root of 645611522 is about 864.2852290805.

The spelling of 645611522 in words is "six hundred forty-five million, six hundred eleven thousand, five hundred twenty-two".