38660221 has 2 divisors, whose sum is σ = 38660222. Its totient is φ = 38660220.

The previous prime is 38660213. The next prime is 38660239. The reversal of 38660221 is 12206683.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36132121 + 2528100 = 6011^2 + 1590^2 .

It is a cyclic number.

It is not a de Polignac number, because 38660221 - 2³ = 38660213 is a prime.

It is a super-2 number, since 2×38660221² = 2989225375537682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 38660221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38660201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19330110 + 19330111.

It is an arithmetic number, because the mean of its divisors is an integer number (19330111).

Almost surely, 2^38660221 is an apocalyptic number.

It is an amenable number.

38660221 is a deficient number, since it is larger than the sum of its proper divisors (1).

38660221 is an equidigital number, since it uses as much as digits as its factorization.

38660221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 38660221 is about 6217.7343944559. The cubic root of 38660221 is about 338.1334306240.

The spelling of 38660221 in words is "thirty-eight million, six hundred sixty thousand, two hundred twenty-one".