21034004231 has 4 divisors (see below), whose sum is σ = 21036420432. Its totient is φ = 21031588032.

The previous prime is 21034004209. The next prime is 21034004261. The reversal of 21034004231 is 13240043012.

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

It is a cyclic number.

It is not a de Polignac number, because 21034004231 - 2¹⁸ = 21033742087 is a prime.

It is a super-2 number, since 2×21034004231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21034004261) 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, 1194995 + ... + 1212468.

It is an arithmetic number, because the mean of its divisors is an integer number (5259105108).

Almost surely, 2^21034004231 is an apocalyptic number.

21034004231 is a deficient number, since it is larger than the sum of its proper divisors (2416201).

21034004231 is an equidigital number, since it uses as much as digits as its factorization.

21034004231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2416200.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21034004231 its reverse (13240043012), we get a palindrome (34274047243).

The spelling of 21034004231 in words is "twenty-one billion, thirty-four million, four thousand, two hundred thirty-one".