21012213331 has 8 divisors (see below), whose sum is σ = 21401418240. Its totient is φ = 20624110728.

The previous prime is 21012213319. The next prime is 21012213337. The reversal of 21012213331 is 13331221012.

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-21012213331 is a prime.

It is a super-2 number, since 2×21012213331² (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 = 21012213299 and 21012213308.

It is not an unprimeable number, because it can be changed into a prime (21012213337) 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 7 ways as a sum of consecutive naturals, for example, 237051 + ... + 313396.

It is an arithmetic number, because the mean of its divisors is an integer number (2675177280).

Almost surely, 2^21012213331 is an apocalyptic number.

21012213331 is a deficient number, since it is larger than the sum of its proper divisors (389204909).

21012213331 is an equidigital number, since it uses as much as digits as its factorization.

21012213331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551153.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21012213331 its reverse (13331221012), we get a palindrome (34343434343).

The spelling of 21012213331 in words is "twenty-one billion, twelve million, two hundred thirteen thousand, three hundred thirty-one".