221161693 has 2 divisors, whose sum is σ = 221161694. Its totient is φ = 221161692.

The previous prime is 221161651. The next prime is 221161709. The reversal of 221161693 is 396161122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 202265284 + 18896409 = 14222^2 + 4347^2 .

It is a cyclic number.

It is not a de Polignac number, because 221161693 - 2⁹ = 221161181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221161613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110580846 + 110580847.

It is an arithmetic number, because the mean of its divisors is an integer number (110580847).

Almost surely, 2^221161693 is an apocalyptic number.

It is an amenable number.

221161693 is a deficient number, since it is larger than the sum of its proper divisors (1).

221161693 is an equidigital number, since it uses as much as digits as its factorization.

221161693 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 31.

The square root of 221161693 is about 14871.5060770589. The cubic root of 221161693 is about 604.7417726390.

The spelling of 221161693 in words is "two hundred twenty-one million, one hundred sixty-one thousand, six hundred ninety-three".