21870509071 has 2 divisors, whose sum is σ = 21870509072. Its totient is φ = 21870509070.

The previous prime is 21870509029. The next prime is 21870509093. The reversal of 21870509071 is 17090507812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21870509071 - 2¹³ = 21870500879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21874509071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10935254535 + 10935254536.

It is an arithmetic number, because the mean of its divisors is an integer number (10935254536).

Almost surely, 2^21870509071 is an apocalyptic number.

21870509071 is a deficient number, since it is larger than the sum of its proper divisors (1).

21870509071 is an equidigital number, since it uses as much as digits as its factorization.

21870509071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 35280, while the sum is 40.

The spelling of 21870509071 in words is "twenty-one billion, eight hundred seventy million, five hundred nine thousand, seventy-one".