37821521 has 2 divisors, whose sum is σ = 37821522. Its totient is φ = 37821520.

The previous prime is 37821491. The next prime is 37821527. The reversal of 37821521 is 12512873.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20349121 + 17472400 = 4511^2 + 4180^2 .

It is a cyclic number.

It is not a de Polignac number, because 37821521 - 2¹⁴ = 37805137 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (37821527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18910760 + 18910761.

It is an arithmetic number, because the mean of its divisors is an integer number (18910761).

Almost surely, 2^37821521 is an apocalyptic number.

It is an amenable number.

37821521 is a deficient number, since it is larger than the sum of its proper divisors (1).

37821521 is an equidigital number, since it uses as much as digits as its factorization.

37821521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 29.

The square root of 37821521 is about 6149.9204059890. The cubic root of 37821521 is about 335.6703618233.

The spelling of 37821521 in words is "thirty-seven million, eight hundred twenty-one thousand, five hundred twenty-one".