1221242444 has 6 divisors (see below), whose sum is σ = 2137174284. Its totient is φ = 610621220.

The previous prime is 1221242411. The next prime is 1221242453. The reversal of 1221242444 is 4442421221.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152655302 + ... + 152655309.

It is an arithmetic number, because the mean of its divisors is an integer number (356195714).

Almost surely, 2^1221242444 is an apocalyptic number.

It is an amenable number.

1221242444 is a deficient number, since it is larger than the sum of its proper divisors (915931840).

1221242444 is a wasteful number, since it uses less digits than its factorization.

1221242444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305310615 (or 305310613 counting only the distinct ones).

The product of its digits is 4096, while the sum is 26.

The square root of 1221242444 is about 34946.2794013898. The cubic root of 1221242444 is about 1068.8923361424.

Adding to 1221242444 its reverse (4442421221), we get a palindrome (5663663665).

The spelling of 1221242444 in words is "one billion, two hundred twenty-one million, two hundred forty-two thousand, four hundred forty-four".