221913247 has 2 divisors, whose sum is σ = 221913248. Its totient is φ = 221913246.

The previous prime is 221913203. The next prime is 221913271. The reversal of 221913247 is 742319122.

221913247 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221913247 - 2²³ = 213524639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221913277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110956623 + 110956624.

It is an arithmetic number, because the mean of its divisors is an integer number (110956624).

Almost surely, 2^221913247 is an apocalyptic number.

221913247 is a deficient number, since it is larger than the sum of its proper divisors (1).

221913247 is an equidigital number, since it uses as much as digits as its factorization.

221913247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 31.

The square root of 221913247 is about 14896.7529012198. The cubic root of 221913247 is about 605.4260114528.

The spelling of 221913247 in words is "two hundred twenty-one million, nine hundred thirteen thousand, two hundred forty-seven".