1221543044 has 12 divisors (see below), whose sum is σ = 2139212544. Its totient is φ = 610339464.

The previous prime is 1221543031. The next prime is 1221543107. The reversal of 1221543044 is 4403451221.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101612 + ... + 112995.

It is an arithmetic number, because the mean of its divisors is an integer number (178267712).

Almost surely, 2^1221543044 is an apocalyptic number.

It is an amenable number.

1221543044 is a deficient number, since it is larger than the sum of its proper divisors (917669500).

1221543044 is a wasteful number, since it uses less digits than its factorization.

1221543044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216034 (or 216032 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 1221543044 is about 34950.5800237993. The cubic root of 1221543044 is about 1068.9800289885.

Adding to 1221543044 its reverse (4403451221), we get a palindrome (5624994265).

The spelling of 1221543044 in words is "one billion, two hundred twenty-one million, five hundred forty-three thousand, forty-four".