21052781371 has 2 divisors, whose sum is σ = 21052781372. Its totient is φ = 21052781370.

The previous prime is 21052781327. The next prime is 21052781389. The reversal of 21052781371 is 17318725012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21052781371 - 2¹⁵ = 21052748603 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21052781371.

It is not a weakly prime, because it can be changed into another prime (21052781671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10526390685 + 10526390686.

It is an arithmetic number, because the mean of its divisors is an integer number (10526390686).

Almost surely, 2^21052781371 is an apocalyptic number.

21052781371 is a deficient number, since it is larger than the sum of its proper divisors (1).

21052781371 is an equidigital number, since it uses as much as digits as its factorization.

21052781371 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23520, while the sum is 37.

The spelling of 21052781371 in words is "twenty-one billion, fifty-two million, seven hundred eighty-one thousand, three hundred seventy-one".