21421735243 has 2 divisors, whose sum is σ = 21421735244. Its totient is φ = 21421735242.

The previous prime is 21421735213. The next prime is 21421735253. The reversal of 21421735243 is 34253712412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21421735243 - 2⁵ = 21421735211 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21421735199 and 21421735208.

It is not a weakly prime, because it can be changed into another prime (21421735213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710867621 + 10710867622.

It is an arithmetic number, because the mean of its divisors is an integer number (10710867622).

Almost surely, 2^21421735243 is an apocalyptic number.

21421735243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21421735243 is an equidigital number, since it uses as much as digits as its factorization.

21421735243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40320, while the sum is 34.

The spelling of 21421735243 in words is "twenty-one billion, four hundred twenty-one million, seven hundred thirty-five thousand, two hundred forty-three".