22019661 has 8 divisors (see below), whose sum is σ = 32621760. Its totient is φ = 14679756.

The previous prime is 22019639. The next prime is 22019677. The reversal of 22019661 is 16691022.

It is not a de Polignac number, because 22019661 - 2¹⁰ = 22018637 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 815543 = 22019661 / (2 + 2 + 0 + 1 + 9 + 6 + 6 + 1).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22019611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 407745 + ... + 407798.

It is an arithmetic number, because the mean of its divisors is an integer number (4077720).

Almost surely, 2^22019661 is an apocalyptic number.

It is an amenable number.

22019661 is a deficient number, since it is larger than the sum of its proper divisors (10602099).

22019661 is an equidigital number, since it uses as much as digits as its factorization.

22019661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 815552 (or 815546 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 22019661 is about 4692.5111614145. The cubic root of 22019661 is about 280.2873792658.

It can be divided in two parts, 220 and 19661, that added together give a square (19881 = 141²).

The spelling of 22019661 in words is "twenty-two million, nineteen thousand, six hundred sixty-one".