21271052777 has 16 divisors (see below), whose sum is σ = 23657598720. Its totient is φ = 19001085312.

The previous prime is 21271052771. The next prime is 21271052813. The reversal of 21271052777 is 77725017212.

It is a cyclic number.

It is not a de Polignac number, because 21271052777 - 2⁸ = 21271052521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21271052771) 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 in 15 ways as a sum of consecutive naturals, for example, 141203 + ... + 249960.

It is an arithmetic number, because the mean of its divisors is an integer number (1478599920).

Almost surely, 2^21271052777 is an apocalyptic number.

It is an amenable number.

21271052777 is a deficient number, since it is larger than the sum of its proper divisors (2386545943).

21271052777 is a wasteful number, since it uses less digits than its factorization.

21271052777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391312.

The product of its (nonzero) digits is 96040, while the sum is 41.

Adding to 21271052777 its reverse (77725017212), we get a palindrome (98996069989).

The spelling of 21271052777 in words is "twenty-one billion, two hundred seventy-one million, fifty-two thousand, seven hundred seventy-seven".