637536685081 has 2 divisors, whose sum is σ = 637536685082. Its totient is φ = 637536685080.

The previous prime is 637536685007. The next prime is 637536685169. The reversal of 637536685081 is 180586635736.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 547512683481 + 90024001600 = 739941^2 + 300040^2 .

It is a cyclic number.

It is not a de Polignac number, because 637536685081 - 2¹¹ = 637536683033 is a prime.

It is a super-2 number, since 2×637536685081² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (637536665081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318768342540 + 318768342541.

It is an arithmetic number, because the mean of its divisors is an integer number (318768342541).

Almost surely, 2^637536685081 is an apocalyptic number.

It is an amenable number.

637536685081 is a deficient number, since it is larger than the sum of its proper divisors (1).

637536685081 is an equidigital number, since it uses as much as digits as its factorization.

637536685081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21772800, while the sum is 58.

The spelling of 637536685081 in words is "six hundred thirty-seven billion, five hundred thirty-six million, six hundred eighty-five thousand, eighty-one".