1221954023 has 4 divisors (see below), whose sum is σ = 1222057200. Its totient is φ = 1221850848.

The previous prime is 1221953989. The next prime is 1221954031. The reversal of 1221954023 is 3204591221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1221954023 - 2¹⁰ = 1221952999 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 (1221954043) 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, 31115 + ... + 58412.

It is an arithmetic number, because the mean of its divisors is an integer number (305514300).

Almost surely, 2^1221954023 is an apocalyptic number.

1221954023 is a deficient number, since it is larger than the sum of its proper divisors (103177).

1221954023 is an equidigital number, since it uses as much as digits as its factorization.

1221954023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103176.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 1221954023 is about 34956.4589596830. The cubic root of 1221954023 is about 1069.0998989855.

The spelling of 1221954023 in words is "one billion, two hundred twenty-one million, nine hundred fifty-four thousand, twenty-three".