1221212023 has 4 divisors (see below), whose sum is σ = 1285486360. Its totient is φ = 1156937688.

The previous prime is 1221211991. The next prime is 1221212029. The reversal of 1221212023 is 3202121221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3202121221 = 13 ⋅246317017.

It is a cyclic number.

It is not a de Polignac number, because 1221212023 - 2⁵ = 1221211991 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221211988 and 1221212006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221212029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32137140 + ... + 32137177.

It is an arithmetic number, because the mean of its divisors is an integer number (321371590).

Almost surely, 2^1221212023 is an apocalyptic number.

1221212023 is a deficient number, since it is larger than the sum of its proper divisors (64274337).

1221212023 is an equidigital number, since it uses as much as digits as its factorization.

1221212023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64274336.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 1221212023 is about 34945.8441449051. The cubic root of 1221212023 is about 1068.8834607429.

Adding to 1221212023 its reverse (3202121221), we get a palindrome (4423333244).

The spelling of 1221212023 in words is "one billion, two hundred twenty-one million, two hundred twelve thousand, twenty-three".