221220469 has 2 divisors, whose sum is σ = 221220470. Its totient is φ = 221220468.

The previous prime is 221220457. The next prime is 221220487. The reversal of 221220469 is 964022122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 180579844 + 40640625 = 13438^2 + 6375^2 .

It is a cyclic number.

It is not a de Polignac number, because 221220469 - 2⁵ = 221220437 is a prime.

It is a super-2 number, since 2×221220469² = 97876991809159922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221220499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110610234 + 110610235.

It is an arithmetic number, because the mean of its divisors is an integer number (110610235).

Almost surely, 2^221220469 is an apocalyptic number.

It is an amenable number.

221220469 is a deficient number, since it is larger than the sum of its proper divisors (1).

221220469 is an equidigital number, since it uses as much as digits as its factorization.

221220469 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 221220469 is about 14873.4820738118. The cubic root of 221220469 is about 604.7953400141.

The spelling of 221220469 in words is "two hundred twenty-one million, two hundred twenty thousand, four hundred sixty-nine".