1211021113 has 4 divisors (see below), whose sum is σ = 1221738228. Its totient is φ = 1200304000.

The previous prime is 1211021111. The next prime is 1211021117. The reversal of 1211021113 is 3111201121.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 575376169 + 635644944 = 23987^2 + 25212^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211021113 - 2¹ = 1211021111 is a prime.

It is a super-2 number, since 2×1211021113² = 2933144272263517538, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211021093 and 1211021102.

It is not an unprimeable number, because it can be changed into a prime (1211021111) 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, 5358388 + ... + 5358613.

It is an arithmetic number, because the mean of its divisors is an integer number (305434557).

Almost surely, 2^1211021113 is an apocalyptic number.

It is an amenable number.

1211021113 is a deficient number, since it is larger than the sum of its proper divisors (10717115).

1211021113 is a wasteful number, since it uses less digits than its factorization.

1211021113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10717114.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1211021113 is about 34799.7286339994. The cubic root of 1211021113 is about 1065.9019046342.

Adding to 1211021113 its reverse (3111201121), we get a palindrome (4322222234).

The spelling of 1211021113 in words is "one billion, two hundred eleven million, twenty-one thousand, one hundred thirteen".