1311101021 has 4 divisors (see below), whose sum is σ = 1311986592. Its totient is φ = 1310215452.

The previous prime is 1311101017. The next prime is 1311101069. The reversal of 1311101021 is 1201011131.

It is a happy number.

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 1311101021 - 2² = 1311101017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1311100993 and 1311101011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311101921) 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, 440561 + ... + 443526.

It is an arithmetic number, because the mean of its divisors is an integer number (327996648).

Almost surely, 2^1311101021 is an apocalyptic number.

It is an amenable number.

1311101021 is a deficient number, since it is larger than the sum of its proper divisors (885571).

1311101021 is an equidigital number, since it uses as much as digits as its factorization.

1311101021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885570.

The product of its (nonzero) digits is 6, while the sum is 11.

The square root of 1311101021 is about 36209.1289732299. The cubic root of 1311101021 is about 1094.4906399913.

Adding to 1311101021 its reverse (1201011131), we get a palindrome (2512112152).

The spelling of 1311101021 in words is "one billion, three hundred eleven million, one hundred one thousand, twenty-one".