37987021 has 2 divisors, whose sum is σ = 37987022. Its totient is φ = 37987020.

The previous prime is 37987003. The next prime is 37987031. The reversal of 37987021 is 12078973.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27352900 + 10634121 = 5230^2 + 3261^2 .

It is a cyclic number.

It is not a de Polignac number, because 37987021 - 2¹⁵ = 37954253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (37987031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18993510 + 18993511.

It is an arithmetic number, because the mean of its divisors is an integer number (18993511).

Almost surely, 2^37987021 is an apocalyptic number.

It is an amenable number.

37987021 is a deficient number, since it is larger than the sum of its proper divisors (1).

37987021 is an equidigital number, since it uses as much as digits as its factorization.

37987021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 37987021 is about 6163.3611771500. The cubic root of 37987021 is about 336.1592599364.

The spelling of 37987021 in words is "thirty-seven million, nine hundred eighty-seven thousand, twenty-one".