21121131331 has 16 divisors (see below), whose sum is σ = 21673672704. Its totient is φ = 20573157024.

The previous prime is 21121131307. The next prime is 21121131337. The reversal of 21121131331 is 13313112112.

It is a cyclic number.

It is not a de Polignac number, because 21121131331 - 2⁹ = 21121130819 is a prime.

It is a super-2 number, since 2×21121131331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121131299 and 21121131308.

It is not an unprimeable number, because it can be changed into a prime (21121131337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10925641 + ... + 10927573.

It is an arithmetic number, because the mean of its divisors is an integer number (1354604544).

Almost surely, 2^21121131331 is an apocalyptic number.

21121131331 is a deficient number, since it is larger than the sum of its proper divisors (552541373).

21121131331 is a wasteful number, since it uses less digits than its factorization.

21121131331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2970.

The product of its digits is 108, while the sum is 19.

Adding to 21121131331 its reverse (13313112112), we get a palindrome (34434243443).

The spelling of 21121131331 in words is "twenty-one billion, one hundred twenty-one million, one hundred thirty-one thousand, three hundred thirty-one".