21437568326243 has 2 divisors, whose sum is σ = 21437568326244. Its totient is φ = 21437568326242.

The previous prime is 21437568326173. The next prime is 21437568326263. The reversal of 21437568326243 is 34262386573412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21437568326243 - 2²⁰ = 21437567277667 is a prime.

It is not a weakly prime, because it can be changed into another prime (21437568326263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10718784163121 + 10718784163122.

It is an arithmetic number, because the mean of its divisors is an integer number (10718784163122).

Almost surely, 2^{21437568326243} is an apocalyptic number.

21437568326243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21437568326243 is an equidigital number, since it uses as much as digits as its factorization.

21437568326243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34836480, while the sum is 56.

The spelling of 21437568326243 in words is "twenty-one trillion, four hundred thirty-seven billion, five hundred sixty-eight million, three hundred twenty-six thousand, two hundred forty-three".