638045161937 has 2 divisors, whose sum is σ = 638045161938. Its totient is φ = 638045161936.

The previous prime is 638045161891. The next prime is 638045162017. The reversal of 638045161937 is 739161540836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 573509348416 + 64535813521 = 757304^2 + 254039^2 .

It is a cyclic number.

It is not a de Polignac number, because 638045161937 - 2¹⁴ = 638045145553 is a prime.

It is not a weakly prime, because it can be changed into another prime (638045161837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319022580968 + 319022580969.

It is an arithmetic number, because the mean of its divisors is an integer number (319022580969).

Almost surely, 2^638045161937 is an apocalyptic number.

It is an amenable number.

638045161937 is a deficient number, since it is larger than the sum of its proper divisors (1).

638045161937 is an equidigital number, since it uses as much as digits as its factorization.

638045161937 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3265920, while the sum is 53.

The spelling of 638045161937 in words is "six hundred thirty-eight billion, forty-five million, one hundred sixty-one thousand, nine hundred thirty-seven".