1221234223420 has 48 divisors (see below), whose sum is σ = 2753696046528. Its totient is φ = 453283281920.

The previous prime is 1221234223393. The next prime is 1221234223511. The reversal of 1221234223420 is 243224321221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25270687 + ... + 25318966.

It is an arithmetic number, because the mean of its divisors is an integer number (57368667636).

Almost surely, 2^{1221234223420} is an apocalyptic number.

1221234223420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221234223420 is an abundant number, since it is smaller than the sum of its proper divisors (1532461823108).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221234223420 is a wasteful number, since it uses less digits than its factorization.

1221234223420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50589750 (or 50589748 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 1221234223420 its reverse (243224321221), we get a palindrome (1464458544641).

The spelling of 1221234223420 in words is "one trillion, two hundred twenty-one billion, two hundred thirty-four million, two hundred twenty-three thousand, four hundred twenty".