1221201022423 has 4 divisors (see below), whose sum is σ = 1221203280088. Its totient is φ = 1221198764760.

The previous prime is 1221201022409. The next prime is 1221201022429. The reversal of 1221201022423 is 3242201021221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221201022423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221201022394 and 1221201022403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221201022429) 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, 218893 + ... + 1578073.

It is an arithmetic number, because the mean of its divisors is an integer number (305300820022).

Almost surely, 2^{1221201022423} is an apocalyptic number.

1221201022423 is a deficient number, since it is larger than the sum of its proper divisors (2257665).

1221201022423 is an equidigital number, since it uses as much as digits as its factorization.

1221201022423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2257664.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 1221201022423 its reverse (3242201021221), we get a palindrome (4463402043644).

The spelling of 1221201022423 in words is "one trillion, two hundred twenty-one billion, two hundred one million, twenty-two thousand, four hundred twenty-three".