1221002453 has 32 divisors (see below), whose sum is σ = 1432166400. Its totient is φ = 1029283200.

The previous prime is 1221002443. The next prime is 1221002473. The reversal of 1221002453 is 3542001221.

It is not a de Polignac number, because 1221002453 - 2⁴ = 1221002437 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221002423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2913878 + ... + 2914296.

It is an arithmetic number, because the mean of its divisors is an integer number (44755200).

Almost surely, 2^1221002453 is an apocalyptic number.

It is an amenable number.

1221002453 is a deficient number, since it is larger than the sum of its proper divisors (211163947).

1221002453 is a wasteful number, since it uses less digits than its factorization.

1221002453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1221002453 is about 34942.8455195051. The cubic root of 1221002453 is about 1068.8223141886.

Adding to 1221002453 its reverse (3542001221), we get a palindrome (4763003674).

The spelling of 1221002453 in words is "one billion, two hundred twenty-one million, two thousand, four hundred fifty-three".