2221405 has 4 divisors (see below), whose sum is σ = 2665692. Its totient is φ = 1777120.

The previous prime is 2221403. The next prime is 2221411. The reversal of 2221405 is 5041222.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5041222 = 2 ⋅2520611.

It can be written as a sum of positive squares in 2 ways, for example, as 1483524 + 737881 = 1218^2 + 859^2 .

It is not a de Polignac number, because 2221405 - 2¹ = 2221403 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 (2221403) 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, 222136 + ... + 222145.

It is an arithmetic number, because the mean of its divisors is an integer number (666423).

2^2221405 is an apocalyptic number.

It is an amenable number.

2221405 is a deficient number, since it is larger than the sum of its proper divisors (444287).

2221405 is an equidigital number, since it uses as much as digits as its factorization.

2221405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444286.

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 2221405 is about 1490.4378551285. The cubic root of 2221405 is about 130.4795894935.

Adding to 2221405 its reverse (5041222), we get a palindrome (7262627).

The spelling of 2221405 in words is "two million, two hundred twenty-one thousand, four hundred five".