1211023213 has 4 divisors (see below), whose sum is σ = 1215628128. Its totient is φ = 1206418300.

The previous prime is 1211023211. The next prime is 1211023223. The reversal of 1211023213 is 3123201121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1211023213 - 2¹ = 1211023211 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 (1211023211) 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, 2302063 + ... + 2302588.

It is an arithmetic number, because the mean of its divisors is an integer number (303907032).

Almost surely, 2^1211023213 is an apocalyptic number.

It is an amenable number.

1211023213 is a deficient number, since it is larger than the sum of its proper divisors (4604915).

1211023213 is an equidigital number, since it uses as much as digits as its factorization.

1211023213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4604914.

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

The square root of 1211023213 is about 34799.7588066354. The cubic root of 1211023213 is about 1065.9025207514.

Adding to 1211023213 its reverse (3123201121), we get a palindrome (4334224334).

The spelling of 1211023213 in words is "one billion, two hundred eleven million, twenty-three thousand, two hundred thirteen".