645137 has 2 divisors, whose sum is σ = 645138. Its totient is φ = 645136.

The previous prime is 645131. The next prime is 645149. The reversal of 645137 is 731546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 410881 + 234256 = 641^2 + 484^2 .

It is a cyclic number.

It is not a de Polignac number, because 645137 - 2⁸ = 644881 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645137.

It is not a weakly prime, because it can be changed into another prime (645131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322568 + 322569.

It is an arithmetic number, because the mean of its divisors is an integer number (322569).

2⁶⁴⁵¹³⁷ is an apocalyptic number.

It is an amenable number.

645137 is a deficient number, since it is larger than the sum of its proper divisors (1).

645137 is an equidigital number, since it uses as much as digits as its factorization.

645137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 26.

The square root of 645137 is about 803.2042081563. The cubic root of 645137 is about 86.4073428402.

The spelling of 645137 in words is "six hundred forty-five thousand, one hundred thirty-seven".