1221214144 has 56 divisors (see below), whose sum is σ = 2487806048. Its totient is φ = 594570240.

The previous prime is 1221214133. The next prime is 1221214199. The reversal of 1221214144 is 4414121221.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400594 + ... + 403630.

It is an arithmetic number, because the mean of its divisors is an integer number (44425108).

Almost surely, 2^1221214144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221214144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1243903024).

1221214144 is an abundant number, since it is smaller than the sum of its proper divisors (1266591904).

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

1221214144 is a wasteful number, since it uses less digits than its factorization.

1221214144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3213 (or 3203 counting only the distinct ones).

The product of its digits is 512, while the sum is 22.

The square root of 1221214144 is about 34945.8744918481. The cubic root of 1221214144 is about 1068.8840795545.

Adding to 1221214144 its reverse (4414121221), we get a palindrome (5635335365).

The spelling of 1221214144 in words is "one billion, two hundred twenty-one million, two hundred fourteen thousand, one hundred forty-four".