221313187 has 2 divisors, whose sum is σ = 221313188. Its totient is φ = 221313186.

The previous prime is 221313179. The next prime is 221313193. The reversal of 221313187 is 781313122.

221313187 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 221313187 - 2³ = 221313179 is a prime.

It is equal to p_12190870 and since 221313187 and 12190870 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (221313167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110656593 + 110656594.

It is an arithmetic number, because the mean of its divisors is an integer number (110656594).

Almost surely, 2^221313187 is an apocalyptic number.

221313187 is a deficient number, since it is larger than the sum of its proper divisors (1).

221313187 is an equidigital number, since it uses as much as digits as its factorization.

221313187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 28.

The square root of 221313187 is about 14876.5986367852. The cubic root of 221313187 is about 604.8798222237.

It can be divided in two parts, 2213 and 13187, that added together give a triangular number (15400 = T₁₇₅).

The spelling of 221313187 in words is "two hundred twenty-one million, three hundred thirteen thousand, one hundred eighty-seven".