1221822438 has 16 divisors (see below), whose sum is σ = 2471102640. Its totient is φ = 402697856.

The previous prime is 1221822391. The next prime is 1221822439. The reversal of 1221822438 is 8342281221.

1221822438 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1221822399 and 1221822408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221822439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1143495 + ... + 1144562.

It is an arithmetic number, because the mean of its divisors is an integer number (154443915).

Almost surely, 2^1221822438 is an apocalyptic number.

1221822438 is an abundant number, since it is smaller than the sum of its proper divisors (1249280202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221822438 is a wasteful number, since it uses less digits than its factorization.

1221822438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2288151.

The product of its digits is 12288, while the sum is 33.

The square root of 1221822438 is about 34954.5767818751. The cubic root of 1221822438 is about 1069.0615225934.

The spelling of 1221822438 in words is "one billion, two hundred twenty-one million, eight hundred twenty-two thousand, four hundred thirty-eight".