645739236 has 24 divisors (see below), whose sum is σ = 1674139040. Its totient is φ = 215246376.

The previous prime is 645739231. The next prime is 645739261. The reversal of 645739236 is 632937546.

It is a junction number, because it is equal to n+sod(n) for n = 645739191 and 645739200.

It is not an unprimeable number, because it can be changed into a prime (645739231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2989426 + ... + 2989641.

Almost surely, 2^645739236 is an apocalyptic number.

It is an amenable number.

645739236 is an abundant number, since it is smaller than the sum of its proper divisors (1028399804).

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

645739236 is a wasteful number, since it uses less digits than its factorization.

645739236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5979080 (or 5979072 counting only the distinct ones).

The product of its digits is 816480, while the sum is 45.

The square root of 645739236 is about 25411.3997253201. The cubic root of 645739236 is about 864.3422159022.

The spelling of 645739236 in words is "six hundred forty-five million, seven hundred thirty-nine thousand, two hundred thirty-six".