21234352031 has 4 divisors (see below), whose sum is σ = 22157584752. Its totient is φ = 20311119312.

The previous prime is 21234352019. The next prime is 21234352039. The reversal of 21234352031 is 13025343212.

It is a happy number.

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

It is not a de Polignac number, because 21234352031 - 2⁶ = 21234351967 is a prime.

It is a super-2 number, since 2×21234352031² (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 (21234352039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 461616326 + ... + 461616371.

It is an arithmetic number, because the mean of its divisors is an integer number (5539396188).

Almost surely, 2^21234352031 is an apocalyptic number.

21234352031 is a deficient number, since it is larger than the sum of its proper divisors (923232721).

21234352031 is an equidigital number, since it uses as much as digits as its factorization.

21234352031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923232720.

The product of its (nonzero) digits is 4320, while the sum is 26.

Adding to 21234352031 its reverse (13025343212), we get a palindrome (34259695243).

The spelling of 21234352031 in words is "twenty-one billion, two hundred thirty-four million, three hundred fifty-two thousand, thirty-one".