1231021213 has 8 divisors (see below), whose sum is σ = 1247417600. Its totient is φ = 1214645328.

The previous prime is 1231021201. The next prime is 1231021237. The reversal of 1231021213 is 3121201321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1231021213 - 2⁹ = 1231020701 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 (1231021273) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 144295 + ... + 152587.

It is an arithmetic number, because the mean of its divisors is an integer number (155927200).

Almost surely, 2^1231021213 is an apocalyptic number.

It is an amenable number.

1231021213 is a deficient number, since it is larger than the sum of its proper divisors (16396387).

1231021213 is an equidigital number, since it uses as much as digits as its factorization.

1231021213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10251.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1231021213 is about 35085.9118878219. The cubic root of 1231021213 is about 1071.7377106338.

Adding to 1231021213 its reverse (3121201321), we get a palindrome (4352222534).

The spelling of 1231021213 in words is "one billion, two hundred thirty-one million, twenty-one thousand, two hundred thirteen".