1221133138 has 8 divisors (see below), whose sum is σ = 1832303088. Its totient is φ = 610365444.

The previous prime is 1221133117. The next prime is 1221133139. The reversal of 1221133138 is 8313311221.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1221133138² = 2982332281443454088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221133139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92856 + ... + 105187.

It is an arithmetic number, because the mean of its divisors is an integer number (229037886).

Almost surely, 2^1221133138 is an apocalyptic number.

1221133138 is a deficient number, since it is larger than the sum of its proper divisors (611169950).

1221133138 is a wasteful number, since it uses less digits than its factorization.

1221133138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201128.

The product of its digits is 864, while the sum is 25.

The square root of 1221133138 is about 34944.7154516960. The cubic root of 1221133138 is about 1068.8604451688.

Adding to 1221133138 its reverse (8313311221), we get a palindrome (9534444359).

The spelling of 1221133138 in words is "one billion, two hundred twenty-one million, one hundred thirty-three thousand, one hundred thirty-eight".