221397477017 has 8 divisors (see below), whose sum is σ = 235610815176. Its totient is φ = 207316356352.

The previous prime is 221397477001. The next prime is 221397477031. The reversal of 221397477017 is 710774793122.

It can be written as a sum of positive squares in 4 ways, for example, as 184581077641 + 36816399376 = 429629^2 + 191876^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221397477017 - 2⁴ = 221397477001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221397477097) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33050918 + ... + 33057615.

It is an arithmetic number, because the mean of its divisors is an integer number (29451351897).

Almost surely, 2^221397477017 is an apocalyptic number.

It is an amenable number.

221397477017 is a deficient number, since it is larger than the sum of its proper divisors (14213338159).

221397477017 is a wasteful number, since it uses less digits than its factorization.

221397477017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66108747.

The product of its (nonzero) digits is 1037232, while the sum is 50.

The spelling of 221397477017 in words is "two hundred twenty-one billion, three hundred ninety-seven million, four hundred seventy-seven thousand, seventeen".