221232769 has 2 divisors, whose sum is σ = 221232770. Its totient is φ = 221232768.

The previous prime is 221232701. The next prime is 221232779. The reversal of 221232769 is 967232122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148352400 + 72880369 = 12180^2 + 8537^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221232769 is a prime.

It is a super-2 number, since 2×221232769² = 97887876158814722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221232779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110616384 + 110616385.

It is an arithmetic number, because the mean of its divisors is an integer number (110616385).

Almost surely, 2^221232769 is an apocalyptic number.

It is an amenable number.

221232769 is a deficient number, since it is larger than the sum of its proper divisors (1).

221232769 is an equidigital number, since it uses as much as digits as its factorization.

221232769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 34.

The square root of 221232769 is about 14873.8955556371. The cubic root of 221232769 is about 604.8065488094.

The spelling of 221232769 in words is "two hundred twenty-one million, two hundred thirty-two thousand, seven hundred sixty-nine".