645111132 has 72 divisors (see below), whose sum is σ = 1565754624. Its totient is φ = 206705088.

The previous prime is 645111127. The next prime is 645111151. The reversal of 645111132 is 231111546.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1757613 + ... + 1757979.

It is an arithmetic number, because the mean of its divisors is an integer number (21746592).

Almost surely, 2^645111132 is an apocalyptic number.

It is an amenable number.

645111132 is an abundant number, since it is smaller than the sum of its proper divisors (920643492).

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

645111132 is a wasteful number, since it uses less digits than its factorization.

645111132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555 (or 516 counting only the distinct ones).

The product of its digits is 720, while the sum is 24.

The square root of 645111132 is about 25399.0380132792. The cubic root of 645111132 is about 864.0618793558.

Adding to 645111132 its reverse (231111546), we get a palindrome (876222678).

The spelling of 645111132 in words is "six hundred forty-five million, one hundred eleven thousand, one hundred thirty-two".