645798990037 has 2 divisors, whose sum is σ = 645798990038. Its totient is φ = 645798990036.

The previous prime is 645798990007. The next prime is 645798990043. The reversal of 645798990037 is 730099897546.

645798990037 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 644208495876 + 1590494161 = 802626^2 + 39881^2 .

It is a cyclic number.

It is not a de Polignac number, because 645798990037 - 2³⁵ = 611439251669 is a prime.

It is a super-2 number, since 2×645798990037² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645798990007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322899495018 + 322899495019.

It is an arithmetic number, because the mean of its divisors is an integer number (322899495019).

Almost surely, 2^645798990037 is an apocalyptic number.

It is an amenable number.

645798990037 is a deficient number, since it is larger than the sum of its proper divisors (1).

645798990037 is an equidigital number, since it uses as much as digits as its factorization.

645798990037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 102876480, while the sum is 67.

The spelling of 645798990037 in words is "six hundred forty-five billion, seven hundred ninety-eight million, nine hundred ninety thousand, thirty-seven".