22221779 has 4 divisors (see below), whose sum is σ = 22232280. Its totient is φ = 22211280.

The previous prime is 22221767. The next prime is 22221781. The reversal of 22221779 is 97712222.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 97712222 = 2 ⋅48856111.

It is a cyclic number.

It is not a de Polignac number, because 22221779 - 2⁸ = 22221523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22221709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 842 + ... + 6719.

It is an arithmetic number, because the mean of its divisors is an integer number (5558070).

Almost surely, 2^22221779 is an apocalyptic number.

22221779 is a deficient number, since it is larger than the sum of its proper divisors (10501).

22221779 is an equidigital number, since it uses as much as digits as its factorization.

22221779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10500.

The product of its digits is 7056, while the sum is 32.

The square root of 22221779 is about 4713.9981968601. The cubic root of 22221779 is about 281.1423526143.

The spelling of 22221779 in words is "twenty-two million, two hundred twenty-one thousand, seven hundred seventy-nine".