21312434011231 has 16 divisors (see below), whose sum is σ = 23496558228000. Its totient is φ = 19169683344000.

The previous prime is 21312434011229. The next prime is 21312434011277. The reversal of 21312434011231 is 13211043421312.

It is a cyclic number.

It is not a de Polignac number, because 21312434011231 - 2¹ = 21312434011229 is a prime.

It is a super-2 number, since 2×21312434011231² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21312434011231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312434011201) 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 15 ways as a sum of consecutive naturals, for example, 5124456 + ... + 8299693.

It is an arithmetic number, because the mean of its divisors is an integer number (1468534889250).

Almost surely, 2^{21312434011231} is an apocalyptic number.

21312434011231 is a deficient number, since it is larger than the sum of its proper divisors (2184124216769).

21312434011231 is a wasteful number, since it uses less digits than its factorization.

21312434011231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13425690.

The product of its (nonzero) digits is 3456, while the sum is 28.

Adding to 21312434011231 its reverse (13211043421312), we get a palindrome (34523477432543).

The spelling of 21312434011231 in words is "twenty-one trillion, three hundred twelve billion, four hundred thirty-four million, eleven thousand, two hundred thirty-one".