21032120231 has 4 divisors (see below), whose sum is σ = 22269303792. Its totient is φ = 19794936672.

The previous prime is 21032120203. The next prime is 21032120251. The reversal of 21032120231 is 13202123012.

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 21032120231 - 2¹⁴ = 21032103847 is a prime.

It is a super-2 number, since 2×21032120231² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1237183543 = 21032120231 / (2 + 1 + 0 + 3 + 2 + 1 + 2 + 0 + 2 + 3 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21032120251) 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, 618591755 + ... + 618591788.

It is an arithmetic number, because the mean of its divisors is an integer number (5567325948).

Almost surely, 2^21032120231 is an apocalyptic number.

21032120231 is a deficient number, since it is larger than the sum of its proper divisors (1237183561).

21032120231 is a wasteful number, since it uses less digits than its factorization.

21032120231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1237183560.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21032120231 its reverse (13202123012), we get a palindrome (34234243243).

The spelling of 21032120231 in words is "twenty-one billion, thirty-two million, one hundred twenty thousand, two hundred thirty-one".