1221021452245 has 16 divisors (see below), whose sum is σ = 1710172297728. Its totient is φ = 819457557120.

The previous prime is 1221021452243. The next prime is 1221021452257. The reversal of 1221021452245 is 5422541201221.

It is not a de Polignac number, because 1221021452245 - 2¹ = 1221021452243 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 (1221021452243) 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, 371129496 + ... + 371132785.

It is an arithmetic number, because the mean of its divisors is an integer number (106885768608).

Almost surely, 2^{1221021452245} is an apocalyptic number.

It is an amenable number.

1221021452245 is a deficient number, since it is larger than the sum of its proper divisors (489150845483).

1221021452245 is an equidigital number, since it uses as much as digits as its factorization.

1221021452245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 742262340.

The product of its (nonzero) digits is 12800, while the sum is 31.

Adding to 1221021452245 its reverse (5422541201221), we get a palindrome (6643562653466).

The spelling of 1221021452245 in words is "one trillion, two hundred twenty-one billion, twenty-one million, four hundred fifty-two thousand, two hundred forty-five".