1216432453 has 4 divisors (see below), whose sum is σ = 1225311660. Its totient is φ = 1207553248.

The previous prime is 1216432447. The next prime is 1216432489. The reversal of 1216432453 is 3542346121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3542346121 = 641 ⋅5526281.

It can be written as a sum of positive squares in 2 ways, for example, as 978563524 + 237868929 = 31282^2 + 15423^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216432453 - 2¹⁷ = 1216301381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216432853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4439398 + ... + 4439671.

It is an arithmetic number, because the mean of its divisors is an integer number (306327915).

Almost surely, 2^1216432453 is an apocalyptic number.

It is an amenable number.

1216432453 is a deficient number, since it is larger than the sum of its proper divisors (8879207).

1216432453 is an equidigital number, since it uses as much as digits as its factorization.

1216432453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8879206.

The product of its digits is 17280, while the sum is 31.

The square root of 1216432453 is about 34877.3917172715. The cubic root of 1216432453 is about 1067.4871750073.

Adding to 1216432453 its reverse (3542346121), we get a palindrome (4758778574).

The spelling of 1216432453 in words is "one billion, two hundred sixteen million, four hundred thirty-two thousand, four hundred fifty-three".