21310123033 has 4 divisors (see below), whose sum is σ = 22563659700. Its totient is φ = 20056586368.

The previous prime is 21310122971. The next prime is 21310123073. The reversal of 21310123033 is 33032101312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8702650944 + 12607472089 = 93288^2 + 112283^2 .

It is a cyclic number.

It is not a de Polignac number, because 21310123033 - 2¹³ = 21310114841 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21310123033.

It is not an unprimeable number, because it can be changed into a prime (21310123073) 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, 626768308 + ... + 626768341.

It is an arithmetic number, because the mean of its divisors is an integer number (5640914925).

Almost surely, 2^21310123033 is an apocalyptic number.

It is an amenable number.

21310123033 is a deficient number, since it is larger than the sum of its proper divisors (1253536667).

21310123033 is a wasteful number, since it uses less digits than its factorization.

21310123033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253536666.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21310123033 its reverse (33032101312), we get a palindrome (54342224345).

The spelling of 21310123033 in words is "twenty-one billion, three hundred ten million, one hundred twenty-three thousand, thirty-three".