37403981 has 2 divisors, whose sum is σ = 37403982. Its totient is φ = 37403980.

The previous prime is 37403921. The next prime is 37403983. The reversal of 37403981 is 18930473.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37319881 + 84100 = 6109^2 + 290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-37403981 is a prime.

It is a super-2 number, since 2×37403981² = 2798115589296722, which contains 22 as substring.

Together with 37403983, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_2284874 and since 37403981 and 2284874 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (37403983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18701990 + 18701991.

It is an arithmetic number, because the mean of its divisors is an integer number (18701991).

Almost surely, 2^37403981 is an apocalyptic number.

It is an amenable number.

37403981 is a deficient number, since it is larger than the sum of its proper divisors (1).

37403981 is an equidigital number, since it uses as much as digits as its factorization.

37403981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 37403981 is about 6115.8794134613. The cubic root of 37403981 is about 334.4305496088.

The spelling of 37403981 in words is "thirty-seven million, four hundred three thousand, nine hundred eighty-one".