38642221 has 2 divisors, whose sum is σ = 38642222. Its totient is φ = 38642220.

The previous prime is 38642209. The next prime is 38642243. The reversal of 38642221 is 12224683.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38378025 + 264196 = 6195^2 + 514^2 .

It is a cyclic number.

It is not a de Polignac number, because 38642221 - 2⁵ = 38642189 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 38642221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38642291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19321110 + 19321111.

It is an arithmetic number, because the mean of its divisors is an integer number (19321111).

Almost surely, 2^38642221 is an apocalyptic number.

It is an amenable number.

38642221 is a deficient number, since it is larger than the sum of its proper divisors (1).

38642221 is an equidigital number, since it uses as much as digits as its factorization.

38642221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 28.

The square root of 38642221 is about 6216.2867533601. The cubic root of 38642221 is about 338.0809447489.

The spelling of 38642221 in words is "thirty-eight million, six hundred forty-two thousand, two hundred twenty-one".