221369761 has 2 divisors, whose sum is σ = 221369762. Its totient is φ = 221369760.

The previous prime is 221369737. The next prime is 221369803. The reversal of 221369761 is 167963122.

221369761 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 137921536 + 83448225 = 11744^2 + 9135^2 .

It is a cyclic number.

It is not a de Polignac number, because 221369761 - 2⁹ = 221369249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221369761.

It is not a weakly prime, because it can be changed into another prime (221360761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110684880 + 110684881.

It is an arithmetic number, because the mean of its divisors is an integer number (110684881).

Almost surely, 2^221369761 is an apocalyptic number.

It is an amenable number.

221369761 is a deficient number, since it is larger than the sum of its proper divisors (1).

221369761 is an equidigital number, since it uses as much as digits as its factorization.

221369761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 37.

The square root of 221369761 is about 14878.4999579931. The cubic root of 221369761 is about 604.9313593779.

The spelling of 221369761 in words is "two hundred twenty-one million, three hundred sixty-nine thousand, seven hundred sixty-one".