221287384429 has 2 divisors, whose sum is σ = 221287384430. Its totient is φ = 221287384428.

The previous prime is 221287384411. The next prime is 221287384441. The reversal of 221287384429 is 924483782122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204697429225 + 16589955204 = 452435^2 + 128802^2 .

It is a cyclic number.

It is not a de Polignac number, because 221287384429 - 2⁵ = 221287384397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221287384529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110643692214 + 110643692215.

It is an arithmetic number, because the mean of its divisors is an integer number (110643692215).

Almost surely, 2^221287384429 is an apocalyptic number.

It is an amenable number.

221287384429 is a deficient number, since it is larger than the sum of its proper divisors (1).

221287384429 is an equidigital number, since it uses as much as digits as its factorization.

221287384429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3096576, while the sum is 52.

The spelling of 221287384429 in words is "two hundred twenty-one billion, two hundred eighty-seven million, three hundred eighty-four thousand, four hundred twenty-nine".