21913454243 has 16 divisors (see below), whose sum is σ = 23607158400. Its totient is φ = 20279413440.

The previous prime is 21913454219. The next prime is 21913454293. The reversal of 21913454243 is 34245431912.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21913454243 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21913454197 and 21913454206.

It is not an unprimeable number, because it can be changed into a prime (21913454293) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62288 + ... + 218418.

It is an arithmetic number, because the mean of its divisors is an integer number (1475447400).

Almost surely, 2^21913454243 is an apocalyptic number.

21913454243 is a deficient number, since it is larger than the sum of its proper divisors (1693704157).

21913454243 is a wasteful number, since it uses less digits than its factorization.

21913454243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156322.

The product of its digits is 103680, while the sum is 38.

The spelling of 21913454243 in words is "twenty-one billion, nine hundred thirteen million, four hundred fifty-four thousand, two hundred forty-three".