2221251613 has 4 divisors (see below), whose sum is σ = 2538573280. Its totient is φ = 1903929948.

The previous prime is 2221251581. The next prime is 2221251619. The reversal of 2221251613 is 3161521222.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3161521222 = 2 ⋅1580760611.

It is a cyclic number.

It is not a de Polignac number, because 2221251613 - 2⁵ = 2221251581 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 (2221251619) 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, 158660823 + ... + 158660836.

It is an arithmetic number, because the mean of its divisors is an integer number (634643320).

Almost surely, 2^2221251613 is an apocalyptic number.

It is an amenable number.

2221251613 is a deficient number, since it is larger than the sum of its proper divisors (317321667).

2221251613 is an equidigital number, since it uses as much as digits as its factorization.

2221251613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317321666.

The product of its digits is 1440, while the sum is 25.

The square root of 2221251613 is about 47130.1560892811. The cubic root of 2221251613 is about 1304.7658623901.

Adding to 2221251613 its reverse (3161521222), we get a palindrome (5382772835).

The spelling of 2221251613 in words is "two billion, two hundred twenty-one million, two hundred fifty-one thousand, six hundred thirteen".