21131412543 has 8 divisors (see below), whose sum is σ = 31305796400. Its totient is φ = 14087608344.

The previous prime is 21131412529. The next prime is 21131412611. The reversal of 21131412543 is 34521413112.

21131412543 is a `hidden beast` number, since 2 + 113 + 1 + 4 + 1 + 2 + 543 = 666.

It is not a de Polignac number, because 21131412543 - 2¹⁴ = 21131396159 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 782644909 = 21131412543 / (2 + 1 + 1 + 3 + 1 + 4 + 1 + 2 + 5 + 4 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131412443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 391322428 + ... + 391322481.

It is an arithmetic number, because the mean of its divisors is an integer number (3913224550).

Almost surely, 2^21131412543 is an apocalyptic number.

21131412543 is a deficient number, since it is larger than the sum of its proper divisors (10174383857).

21131412543 is an equidigital number, since it uses as much as digits as its factorization.

21131412543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782644918 (or 782644912 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

Adding to 21131412543 its reverse (34521413112), we get a palindrome (55652825655).

The spelling of 21131412543 in words is "twenty-one billion, one hundred thirty-one million, four hundred twelve thousand, five hundred forty-three".