1221200355423 has 16 divisors (see below), whose sum is σ = 1714872902400. Its totient is φ = 770876064000.

The previous prime is 1221200355379. The next prime is 1221200355469. The reversal of 1221200355423 is 3245530021221.

It is not a de Polignac number, because 1221200355423 - 2¹⁰ = 1221200354399 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221200355623) 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, 5563203 + ... + 5778548.

It is an arithmetic number, because the mean of its divisors is an integer number (107179556400).

Almost surely, 2^{1221200355423} is an apocalyptic number.

1221200355423 is a deficient number, since it is larger than the sum of its proper divisors (493672546977).

1221200355423 is a wasteful number, since it uses less digits than its factorization.

1221200355423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11343662.

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 1221200355423 its reverse (3245530021221), we get a palindrome (4466730376644).

The spelling of 1221200355423 in words is "one trillion, two hundred twenty-one billion, two hundred million, three hundred fifty-five thousand, four hundred twenty-three".