221415281 has 2 divisors, whose sum is σ = 221415282. Its totient is φ = 221415280.

The previous prime is 221415277. The next prime is 221415287. The reversal of 221415281 is 182514122.

221415281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 175297600 + 46117681 = 13240^2 + 6791^2 .

It is a cyclic number.

It is not a de Polignac number, because 221415281 - 2² = 221415277 is a prime.

It is a super-2 number, since 2×221415281² = 98049453320617922, which contains 22 as substring.

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 221415281.

It is not a weakly prime, because it can be changed into another prime (221415287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110707640 + 110707641.

It is an arithmetic number, because the mean of its divisors is an integer number (110707641).

Almost surely, 2^221415281 is an apocalyptic number.

It is an amenable number.

221415281 is a deficient number, since it is larger than the sum of its proper divisors (1).

221415281 is an equidigital number, since it uses as much as digits as its factorization.

221415281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1280, while the sum is 26.

The square root of 221415281 is about 14880.0296034652. The cubic root of 221415281 is about 604.9728203076.

The spelling of 221415281 in words is "two hundred twenty-one million, four hundred fifteen thousand, two hundred eighty-one".