1220321231 has 4 divisors (see below), whose sum is σ = 1259686464. Its totient is φ = 1180956000.

The previous prime is 1220321203. The next prime is 1220321261. The reversal of 1220321231 is 1321230221.

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

It is a cyclic number.

It is not a de Polignac number, because 1220321231 - 2²⁶ = 1153212367 is a prime.

It is a super-2 number, since 2×1220321231² = 2978367813658710722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220321261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19682570 + ... + 19682631.

It is an arithmetic number, because the mean of its divisors is an integer number (314921616).

Almost surely, 2^1220321231 is an apocalyptic number.

1220321231 is a deficient number, since it is larger than the sum of its proper divisors (39365233).

1220321231 is an equidigital number, since it uses as much as digits as its factorization.

1220321231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39365232.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1220321231 is about 34933.0964988791. The cubic root of 1220321231 is about 1068.6235046713.

Adding to 1220321231 its reverse (1321230221), we get a palindrome (2541551452).

The spelling of 1220321231 in words is "one billion, two hundred twenty million, three hundred twenty-one thousand, two hundred thirty-one".