2215041221 has 4 divisors (see below), whose sum is σ = 2216315244. Its totient is φ = 2213767200.

The previous prime is 2215041203. The next prime is 2215041247. The reversal of 2215041221 is 1221405122.

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 144336196 + 2070705025 = 12014^2 + 45505^2 .

It is a cyclic number.

It is not a de Polignac number, because 2215041221 - 2¹⁴ = 2215024837 is a prime.

It is a super-2 number, since 2×2215041221² = 9812815221458341682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2215041193 and 2215041202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2215041281) 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, 634400 + ... + 637881.

It is an arithmetic number, because the mean of its divisors is an integer number (554078811).

Almost surely, 2^2215041221 is an apocalyptic number.

It is an amenable number.

2215041221 is a deficient number, since it is larger than the sum of its proper divisors (1274023).

2215041221 is a wasteful number, since it uses less digits than its factorization.

2215041221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1274022.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 2215041221 is about 47064.2244279028. The cubic root of 2215041221 is about 1303.5487301215.

Adding to 2215041221 its reverse (1221405122), we get a palindrome (3436446343).

The spelling of 2215041221 in words is "two billion, two hundred fifteen million, forty-one thousand, two hundred twenty-one".