1311122021 has 8 divisors (see below), whose sum is σ = 1430605344. Its totient is φ = 1191687120.

The previous prime is 1311122009. The next prime is 1311122023. The reversal of 1311122021 is 1202211131.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311122021 is a prime.

It is a super-4 number, since 4×1311122021⁴ (a number of 38 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1311121987 and 1311122005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311122023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67055 + ... + 84371.

It is an arithmetic number, because the mean of its divisors is an integer number (178825668).

Almost surely, 2^1311122021 is an apocalyptic number.

1311122021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1311122021 is a deficient number, since it is larger than the sum of its proper divisors (119483323).

1311122021 is a wasteful number, since it uses less digits than its factorization.

1311122021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24211.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 1311122021 is about 36209.4189541893. The cubic root of 1311122021 is about 1094.4964834721.

Adding to 1311122021 its reverse (1202211131), we get a palindrome (2513333152).

The spelling of 1311122021 in words is "one billion, three hundred eleven million, one hundred twenty-two thousand, twenty-one".