37309981 has 2 divisors, whose sum is σ = 37309982. Its totient is φ = 37309980.

The previous prime is 37309973. The next prime is 37309991. The reversal of 37309981 is 18990373.

37309981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32319225 + 4990756 = 5685^2 + 2234^2 .

It is an emirp because it is prime and its reverse (18990373) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 37309981 - 2³ = 37309973 is a prime.

It is a super-2 number, since 2×37309981² = 2784069364440722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (37309991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18654990 + 18654991.

It is an arithmetic number, because the mean of its divisors is an integer number (18654991).

Almost surely, 2^37309981 is an apocalyptic number.

It is an amenable number.

37309981 is a deficient number, since it is larger than the sum of its proper divisors (1).

37309981 is an equidigital number, since it uses as much as digits as its factorization.

37309981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 37309981 is about 6108.1896663414. The cubic root of 37309981 is about 334.1501619602.

The spelling of 37309981 in words is "thirty-seven million, three hundred nine thousand, nine hundred eighty-one".