221740693 has 2 divisors, whose sum is σ = 221740694. Its totient is φ = 221740692.

The previous prime is 221740663. The next prime is 221740789. The reversal of 221740693 is 396047122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216619524 + 5121169 = 14718^2 + 2263^2 .

It is a cyclic number.

It is not a de Polignac number, because 221740693 - 2⁵ = 221740661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221740663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110870346 + 110870347.

It is an arithmetic number, because the mean of its divisors is an integer number (110870347).

Almost surely, 2^221740693 is an apocalyptic number.

It is an amenable number.

221740693 is a deficient number, since it is larger than the sum of its proper divisors (1).

221740693 is an equidigital number, since it uses as much as digits as its factorization.

221740693 is an evil number, because the sum of its binary digits is even.

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

The square root of 221740693 is about 14890.9601100802. The cubic root of 221740693 is about 605.2690495612.

The spelling of 221740693 in words is "two hundred twenty-one million, seven hundred forty thousand, six hundred ninety-three".