1243221231 has 16 divisors (see below), whose sum is σ = 1976799744. Its totient is φ = 679524384.

The previous prime is 1243221223. The next prime is 1243221253. The reversal of 1243221231 is 1321223421.

It is not a de Polignac number, because 1243221231 - 2³ = 1243221223 is a prime.

It is a super-2 number, since 2×1243221231² = 3091198058418310722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 1243221198 and 1243221207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243221131) 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, 1286496 + ... + 1287461.

It is an arithmetic number, because the mean of its divisors is an integer number (123549984).

Almost surely, 2^1243221231 is an apocalyptic number.

1243221231 is a deficient number, since it is larger than the sum of its proper divisors (733578513).

1243221231 is a wasteful number, since it uses less digits than its factorization.

1243221231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2573990.

The product of its digits is 576, while the sum is 21.

The square root of 1243221231 is about 35259.3424640903. The cubic root of 1243221231 is about 1075.2665590288.

Adding to 1243221231 its reverse (1321223421), we get a palindrome (2564444652).

The spelling of 1243221231 in words is "one billion, two hundred forty-three million, two hundred twenty-one thousand, two hundred thirty-one".