21011304231 has 32 divisors (see below), whose sum is σ = 31602278400. Its totient is φ = 13795596000.

The previous prime is 21011304229. The next prime is 21011304233. The reversal of 21011304231 is 13240311012.

21011304231 is a `hidden beast` number, since 210 + 1 + 1 + 30 + 423 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (21011304229) and next prime (21011304233).

It is not a de Polignac number, because 21011304231 - 2¹ = 21011304229 is a prime.

It is a super-2 number, since 2×21011304231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011304233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 470106 + ... + 512856.

It is an arithmetic number, because the mean of its divisors is an integer number (987571200).

Almost surely, 2^21011304231 is an apocalyptic number.

21011304231 is a deficient number, since it is larger than the sum of its proper divisors (10590974169).

21011304231 is a wasteful number, since it uses less digits than its factorization.

21011304231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43036 (or 43030 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21011304231 its reverse (13240311012), we get a palindrome (34251615243).

The spelling of 21011304231 in words is "twenty-one billion, eleven million, three hundred four thousand, two hundred thirty-one".