21040001233 has 4 divisors (see below), whose sum is σ = 21384919348. Its totient is φ = 20695083120.

The previous prime is 21040001221. The next prime is 21040001237. The reversal of 21040001233 is 33210004012.

It is a happy number.

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 1385923984 + 19654077249 = 37228^2 + 140193^2 .

It is a cyclic number.

It is not a de Polignac number, because 21040001233 - 2¹³ = 21039993041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21040001237) 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, 172458966 + ... + 172459087.

It is an arithmetic number, because the mean of its divisors is an integer number (5346229837).

Almost surely, 2^21040001233 is an apocalyptic number.

It is an amenable number.

21040001233 is a deficient number, since it is larger than the sum of its proper divisors (344918115).

21040001233 is an equidigital number, since it uses as much as digits as its factorization.

21040001233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344918114.

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21040001233 its reverse (33210004012), we get a palindrome (54250005245).

The spelling of 21040001233 in words is "twenty-one billion, forty million, one thousand, two hundred thirty-three".