21375145233 has 12 divisors (see below), whose sum is σ = 33250226100. Its totient is φ = 13153935456.

The previous prime is 21375145229. The next prime is 21375145241. The reversal of 21375145233 is 33254157312.

21375145233 is a `hidden beast` number, since 2 + 137 + 514 + 5 + 2 + 3 + 3 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8958054609 + 12417090624 = 94647^2 + 111432^2 .

It is not a de Polignac number, because 21375145233 - 2² = 21375145229 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21375145433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91346658 + ... + 91346891.

It is an arithmetic number, because the mean of its divisors is an integer number (2770852175).

Almost surely, 2^21375145233 is an apocalyptic number.

It is an amenable number.

21375145233 is a deficient number, since it is larger than the sum of its proper divisors (11875080867).

21375145233 is a wasteful number, since it uses less digits than its factorization.

21375145233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182693568 (or 182693565 counting only the distinct ones).

The product of its digits is 75600, while the sum is 36.

The spelling of 21375145233 in words is "twenty-one billion, three hundred seventy-five million, one hundred forty-five thousand, two hundred thirty-three".