1221154453 has 8 divisors (see below), whose sum is σ = 1285956000. Its totient is φ = 1156405968.

The previous prime is 1221154409. The next prime is 1221154483. The reversal of 1221154453 is 3544511221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221154453 - 2²⁵ = 1187600021 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 (1221154483) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39375 + ... + 63187.

It is an arithmetic number, because the mean of its divisors is an integer number (160744500).

Almost surely, 2^1221154453 is an apocalyptic number.

It is an amenable number.

1221154453 is a deficient number, since it is larger than the sum of its proper divisors (64801547).

1221154453 is a wasteful number, since it uses less digits than its factorization.

1221154453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26531.

The product of its digits is 4800, while the sum is 28.

The square root of 1221154453 is about 34945.0204321016. The cubic root of 1221154453 is about 1068.8666641543.

Adding to 1221154453 its reverse (3544511221), we get a palindrome (4765665674).

The spelling of 1221154453 in words is "one billion, two hundred twenty-one million, one hundred fifty-four thousand, four hundred fifty-three".