189214661221 has 2 divisors, whose sum is σ = 189214661222. Its totient is φ = 189214661220.

The previous prime is 189214661183. The next prime is 189214661243. The reversal of 189214661221 is 122166412981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 179573385121 + 9641276100 = 423761^2 + 98190^2 .

It is an emirp because it is prime and its reverse (122166412981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 189214661221 - 2³³ = 180624726629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (189214661521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94607330610 + 94607330611.

It is an arithmetic number, because the mean of its divisors is an integer number (94607330611).

Almost surely, 2^189214661221 is an apocalyptic number.

It is an amenable number.

189214661221 is a deficient number, since it is larger than the sum of its proper divisors (1).

189214661221 is an equidigital number, since it uses as much as digits as its factorization.

189214661221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 43.

The spelling of 189214661221 in words is "one hundred eighty-nine billion, two hundred fourteen million, six hundred sixty-one thousand, two hundred twenty-one".