221071693 has 4 divisors (see below), whose sum is σ = 221139100. Its totient is φ = 221004288.

The previous prime is 221071651. The next prime is 221071703. The reversal of 221071693 is 396170122.

221071693 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 63393444 + 157678249 = 7962^2 + 12557^2 .

It is a cyclic number.

It is not a de Polignac number, because 221071693 - 2²⁵ = 187517261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221075693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28518 + ... + 35431.

It is an arithmetic number, because the mean of its divisors is an integer number (55284775).

Almost surely, 2^221071693 is an apocalyptic number.

It is an amenable number.

221071693 is a deficient number, since it is larger than the sum of its proper divisors (67407).

221071693 is an equidigital number, since it uses as much as digits as its factorization.

221071693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67406.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 221071693 is about 14868.4798483234. The cubic root of 221071693 is about 604.6597298836.

The spelling of 221071693 in words is "two hundred twenty-one million, seventy-one thousand, six hundred ninety-three".