1221440442 has 16 divisors (see below), whose sum is σ = 2449331040. Its totient is φ = 406071792.

The previous prime is 1221440431. The next prime is 1221440443. The reversal of 1221440442 is 2440441221.

It is not an unprimeable number, because it can be changed into a prime (1221440443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266293 + ... + 270840.

It is an arithmetic number, because the mean of its divisors is an integer number (153083190).

Almost surely, 2^1221440442 is an apocalyptic number.

1221440442 is an abundant number, since it is smaller than the sum of its proper divisors (1227890598).

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

1221440442 is a wasteful number, since it uses less digits than its factorization.

1221440442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537517.

The product of its (nonzero) digits is 2048, while the sum is 24.

The square root of 1221440442 is about 34949.1121775647. The cubic root of 1221440442 is about 1068.9500989312.

Adding to 1221440442 its reverse (2440441221), we get a palindrome (3661881663).

The spelling of 1221440442 in words is "one billion, two hundred twenty-one million, four hundred forty thousand, four hundred forty-two".