37943681 has 2 divisors, whose sum is σ = 37943682. Its totient is φ = 37943680.

The previous prime is 37943671. The next prime is 37943683. The reversal of 37943681 is 18634973.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33466225 + 4477456 = 5785^2 + 2116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-37943681 is a prime.

It is a super-2 number, since 2×37943681² = 2879445855659522, which contains 22 as substring.

Together with 37943683, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (37943683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18971840 + 18971841.

It is an arithmetic number, because the mean of its divisors is an integer number (18971841).

Almost surely, 2^37943681 is an apocalyptic number.

It is an amenable number.

37943681 is a deficient number, since it is larger than the sum of its proper divisors (1).

37943681 is an equidigital number, since it uses as much as digits as its factorization.

37943681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 37943681 is about 6159.8442350436. The cubic root of 37943681 is about 336.0313681268.

The spelling of 37943681 in words is "thirty-seven million, nine hundred forty-three thousand, six hundred eighty-one".