11215621 has 4 divisors (see below), whose sum is σ = 11232544. Its totient is φ = 11198700.

The previous prime is 11215619. The next prime is 11215627. The reversal of 11215621 is 12651211.

11215621 is digitally balanced in base 3, 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, 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: 12651211 = 1021 ⋅12391.

It is a cyclic number.

It is not a de Polignac number, because 11215621 - 2¹ = 11215619 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 (11215627) 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, 7425 + ... + 8806.

It is an arithmetic number, because the mean of its divisors is an integer number (2808136).

Almost surely, 2^11215621 is an apocalyptic number.

It is an amenable number.

11215621 is a deficient number, since it is larger than the sum of its proper divisors (16923).

11215621 is an equidigital number, since it uses as much as digits as its factorization.

11215621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16922.

The product of its digits is 120, while the sum is 19.

The square root of 11215621 is about 3348.9731261985. The cubic root of 11215621 is about 223.8417581896.

Adding to 11215621 its reverse (12651211), we get a palindrome (23866832).

The spelling of 11215621 in words is "eleven million, two hundred fifteen thousand, six hundred twenty-one".