1221363453 has 16 divisors (see below), whose sum is σ = 1815030720. Its totient is φ = 726011136.

The previous prime is 1221363439. The next prime is 1221363497. The reversal of 1221363453 is 3543631221.

It is not a de Polignac number, because 1221363453 - 2¹² = 1221359357 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221363453.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221363433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 629250 + ... + 631187.

It is an arithmetic number, because the mean of its divisors is an integer number (113439420).

Almost surely, 2^1221363453 is an apocalyptic number.

It is an amenable number.

1221363453 is a deficient number, since it is larger than the sum of its proper divisors (593667267).

1221363453 is a wasteful number, since it uses less digits than its factorization.

1221363453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1260476.

The product of its digits is 12960, while the sum is 30.

The square root of 1221363453 is about 34948.0107159192. The cubic root of 1221363453 is about 1068.9276393484.

Adding to 1221363453 its reverse (3543631221), we get a palindrome (4764994674).

The spelling of 1221363453 in words is "one billion, two hundred twenty-one million, three hundred sixty-three thousand, four hundred fifty-three".