21251419771 has 2 divisors, whose sum is σ = 21251419772. Its totient is φ = 21251419770.

The previous prime is 21251419753. The next prime is 21251419807. The reversal of 21251419771 is 17791415212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21251419771 - 2⁷ = 21251419643 is a prime.

It is not a weakly prime, because it can be changed into another prime (21251419171) 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, 10625709885 + 10625709886.

It is an arithmetic number, because the mean of its divisors is an integer number (10625709886).

Almost surely, 2^21251419771 is an apocalyptic number.

21251419771 is a deficient number, since it is larger than the sum of its proper divisors (1).

21251419771 is an equidigital number, since it uses as much as digits as its factorization.

21251419771 is an odious number, because the sum of its binary digits is odd.

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

The spelling of 21251419771 in words is "twenty-one billion, two hundred fifty-one million, four hundred nineteen thousand, seven hundred seventy-one".