1231213311 has 32 divisors (see below), whose sum is σ = 1850900480. Its totient is φ = 808805088.

The previous prime is 1231213303. The next prime is 1231213327. The reversal of 1231213311 is 1133121321.

It is not a de Polignac number, because 1231213311 - 2³ = 1231213303 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 (1231213411) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 537210 + ... + 539496.

It is an arithmetic number, because the mean of its divisors is an integer number (57840640).

Almost surely, 2^1231213311 is an apocalyptic number.

1231213311 is a deficient number, since it is larger than the sum of its proper divisors (619687169).

1231213311 is a wasteful number, since it uses less digits than its factorization.

1231213311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2580 (or 2574 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 1231213311 is about 35088.6493185474. The cubic root of 1231213311 is about 1071.7934551275.

Adding to 1231213311 its reverse (1133121321), we get a palindrome (2364334632).

The spelling of 1231213311 in words is "one billion, two hundred thirty-one million, two hundred thirteen thousand, three hundred eleven".