37993981581 has 80 divisors (see below), whose sum is σ = 62658028224. Its totient is φ = 22843731456.

The previous prime is 37993981561. The next prime is 37993981591. The reversal of 37993981581 is 18518939973.

37993981581 is a `hidden beast` number, since 3 + 7 + 99 + 398 + 158 + 1 = 666.

It is not a de Polignac number, because 37993981581 - 2¹⁴ = 37993965197 is a prime.

It is a super-2 number, since 2×37993981581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (37993981561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3132130 + ... + 3144236.

Almost surely, 2^37993981581 is an apocalyptic number.

It is an amenable number.

37993981581 is a deficient number, since it is larger than the sum of its proper divisors (24664046643).

37993981581 is a wasteful number, since it uses less digits than its factorization.

37993981581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12232 (or 12223 counting only the distinct ones).

The product of its digits is 14696640, while the sum is 63.

The spelling of 37993981581 in words is "thirty-seven billion, nine hundred ninety-three million, nine hundred eighty-one thousand, five hundred eighty-one".