21312311033 has 8 divisors (see below), whose sum is σ = 23743158600. Its totient is φ = 18994526208.

The previous prime is 21312311011. The next prime is 21312311093. The reversal of 21312311033 is 33011321312.

It can be written as a sum of positive squares in 4 ways, for example, as 2943388009 + 18368923024 = 54253^2 + 135532^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21312311033 - 2⁶ = 21312310969 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21312310996 and 21312311014.

It is not an unprimeable number, because it can be changed into a prime (21312311093) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28265288 + ... + 28266041.

It is an arithmetic number, because the mean of its divisors is an integer number (2967894825).

Almost surely, 2^21312311033 is an apocalyptic number.

It is an amenable number.

21312311033 is a deficient number, since it is larger than the sum of its proper divisors (2430847567).

21312311033 is a wasteful number, since it uses less digits than its factorization.

21312311033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56531371.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 21312311033 its reverse (33011321312), we get a palindrome (54323632345).

The spelling of 21312311033 in words is "twenty-one billion, three hundred twelve million, three hundred eleven thousand, thirty-three".