21275787443 has 2 divisors, whose sum is σ = 21275787444. Its totient is φ = 21275787442.

The previous prime is 21275787431. The next prime is 21275787473. The reversal of 21275787443 is 34478757212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21275787443 - 2¹⁰ = 21275786419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21275787391 and 21275787400.

It is not a weakly prime, because it can be changed into another prime (21275787473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10637893721 + 10637893722.

It is an arithmetic number, because the mean of its divisors is an integer number (10637893722).

Almost surely, 2^21275787443 is an apocalyptic number.

21275787443 is a deficient number, since it is larger than the sum of its proper divisors (1).

21275787443 is an equidigital number, since it uses as much as digits as its factorization.

21275787443 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2634240, while the sum is 50.

The spelling of 21275787443 in words is "twenty-one billion, two hundred seventy-five million, seven hundred eighty-seven thousand, four hundred forty-three".