909252221 has 2 divisors, whose sum is σ = 909252222. Its totient is φ = 909252220.

The previous prime is 909252209. The next prime is 909252229. The reversal of 909252221 is 122252909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 692426596 + 216825625 = 26314^2 + 14725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-909252221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (909252229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 454626110 + 454626111.

It is an arithmetic number, because the mean of its divisors is an integer number (454626111).

Almost surely, 2^909252221 is an apocalyptic number.

It is an amenable number.

909252221 is a deficient number, since it is larger than the sum of its proper divisors (1).

909252221 is an equidigital number, since it uses as much as digits as its factorization.

909252221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 909252221 is about 30153.8093945027. The cubic root of 909252221 is about 968.7866008731.

The spelling of 909252221 in words is "nine hundred nine million, two hundred fifty-two thousand, two hundred twenty-one".