1221118842 has 16 divisors (see below), whose sum is σ = 2443226400. Its totient is φ = 406874832.

The previous prime is 1221118837. The next prime is 1221118849. The reversal of 1221118842 is 2488111221.

It is a super-2 number, since 2×1221118842² = 2982262452574841928, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221118849) 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, 24628 + ... + 55215.

It is an arithmetic number, because the mean of its divisors is an integer number (152701650).

Almost surely, 2^1221118842 is an apocalyptic number.

1221118842 is an abundant number, since it is smaller than the sum of its proper divisors (1222107558).

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

1221118842 is a wasteful number, since it uses less digits than its factorization.

1221118842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82397.

The product of its digits is 2048, while the sum is 30.

The square root of 1221118842 is about 34944.5108994245. The cubic root of 1221118842 is about 1068.8562740461.

The spelling of 1221118842 in words is "one billion, two hundred twenty-one million, one hundred eighteen thousand, eight hundred forty-two".