645122523 has 24 divisors (see below), whose sum is σ = 910821648. Its totient is φ = 406099008.

The previous prime is 645122521. The next prime is 645122531. The reversal of 645122523 is 325221546.

It is not a de Polignac number, because 645122523 - 2¹ = 645122521 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645122521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 403161 + ... + 404757.

It is an arithmetic number, because the mean of its divisors is an integer number (37950902).

Almost surely, 2^645122523 is an apocalyptic number.

645122523 is a deficient number, since it is larger than the sum of its proper divisors (265699125).

645122523 is a wasteful number, since it uses less digits than its factorization.

645122523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2011 (or 1992 counting only the distinct ones).

The product of its digits is 14400, while the sum is 30.

The square root of 645122523 is about 25399.2622530655. The cubic root of 645122523 is about 864.0669650279.

The spelling of 645122523 in words is "six hundred forty-five million, one hundred twenty-two thousand, five hundred twenty-three".