21250134043423 has 4 divisors (see below), whose sum is σ = 21250245398128. Its totient is φ = 21250022688720.

The previous prime is 21250134043421. The next prime is 21250134043429. The reversal of 21250134043423 is 32434043105212.

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 21250134043423 - 2¹ = 21250134043421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21250134043421) 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, 55390611 + ... + 55772932.

It is an arithmetic number, because the mean of its divisors is an integer number (5312561349532).

Almost surely, 2^{21250134043423} is an apocalyptic number.

21250134043423 is a deficient number, since it is larger than the sum of its proper divisors (111354705).

21250134043423 is a wasteful number, since it uses less digits than its factorization.

21250134043423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111354704.

The product of its (nonzero) digits is 69120, while the sum is 34.

Adding to 21250134043423 its reverse (32434043105212), we get a palindrome (53684177148635).

The spelling of 21250134043423 in words is "twenty-one trillion, two hundred fifty billion, one hundred thirty-four million, forty-three thousand, four hundred twenty-three".