37872438581 has 2 divisors, whose sum is σ = 37872438582. Its totient is φ = 37872438580.

The previous prime is 37872438547. The next prime is 37872438623. The reversal of 37872438581 is 18583427873.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24493815025 + 13378623556 = 156505^2 + 115666^2 .

It is a cyclic number.

It is not a de Polignac number, because 37872438581 - 2¹⁰ = 37872437557 is a prime.

It is a super-2 number, since 2×37872438581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (37872438521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18936219290 + 18936219291.

It is an arithmetic number, because the mean of its divisors is an integer number (18936219291).

Almost surely, 2^37872438581 is an apocalyptic number.

It is an amenable number.

37872438581 is a deficient number, since it is larger than the sum of its proper divisors (1).

37872438581 is an equidigital number, since it uses as much as digits as its factorization.

37872438581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9031680, while the sum is 56.

The spelling of 37872438581 in words is "thirty-seven billion, eight hundred seventy-two million, four hundred thirty-eight thousand, five hundred eighty-one".