221252081 has 2 divisors, whose sum is σ = 221252082. Its totient is φ = 221252080.

The previous prime is 221252039. The next prime is 221252147. The reversal of 221252081 is 180252122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196252081 + 25000000 = 14009^2 + 5000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221252081 is a prime.

It is a super-2 number, since 2×221252081² = 97904966693661122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221252011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110626040 + 110626041.

It is an arithmetic number, because the mean of its divisors is an integer number (110626041).

Almost surely, 2^221252081 is an apocalyptic number.

It is an amenable number.

221252081 is a deficient number, since it is larger than the sum of its proper divisors (1).

221252081 is an equidigital number, since it uses as much as digits as its factorization.

221252081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 221252081 is about 14874.5447325288. The cubic root of 221252081 is about 604.8241466910.

The spelling of 221252081 in words is "two hundred twenty-one million, two hundred fifty-two thousand, eighty-one".