645233737 has 2 divisors, whose sum is σ = 645233738. Its totient is φ = 645233736.

The previous prime is 645233689. The next prime is 645233741. The reversal of 645233737 is 737332546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 467251456 + 177982281 = 21616^2 + 13341^2 .

It is a cyclic number.

It is not a de Polignac number, because 645233737 - 2⁷ = 645233609 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645233737.

It is not a weakly prime, because it can be changed into another prime (645233767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322616868 + 322616869.

It is an arithmetic number, because the mean of its divisors is an integer number (322616869).

Almost surely, 2^645233737 is an apocalyptic number.

It is an amenable number.

645233737 is a deficient number, since it is larger than the sum of its proper divisors (1).

645233737 is an equidigital number, since it uses as much as digits as its factorization.

645233737 is an evil number, because the sum of its binary digits is even.

The product of its digits is 317520, while the sum is 40.

The square root of 645233737 is about 25401.4514742760. The cubic root of 645233737 is about 864.1166149360.

The spelling of 645233737 in words is "six hundred forty-five million, two hundred thirty-three thousand, seven hundred thirty-seven".