18221227739 has 48 divisors (see below), whose sum is σ = 22710977856. Its totient is φ = 14493050880.

The previous prime is 18221227729. The next prime is 18221227789. The reversal of 18221227739 is 93772212281.

It is not a de Polignac number, because 18221227739 - 2⁸ = 18221227483 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18221227739.

It is not an unprimeable number, because it can be changed into a prime (18221227729) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4085999 + ... + 4090455.

It is an arithmetic number, because the mean of its divisors is an integer number (473145372).

Almost surely, 2^18221227739 is an apocalyptic number.

18221227739 is a deficient number, since it is larger than the sum of its proper divisors (4489750117).

18221227739 is a wasteful number, since it uses less digits than its factorization.

18221227739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4628 (or 4617 counting only the distinct ones).

The product of its digits is 169344, while the sum is 44.

The spelling of 18221227739 in words is "eighteen billion, two hundred twenty-one million, two hundred twenty-seven thousand, seven hundred thirty-nine".