21275995733281 has 9 divisors (see below), whose sum is σ = 21296342856691. Its totient is φ = 21255668044744.

The previous prime is 21275995733269. The next prime is 21275995733371. The reversal of 21275995733281 is 18233759957212.

The square root of 21275995733281 is 4612591.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 3999836001681 + 17276159731600 = 1999959^2 + 4156460^2 .

It is not a de Polignac number, because 21275995733281 - 2⁵ = 21275995733249 is a prime.

It is a super-2 number, since 2×21275995733281² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21275995733081) 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 in 8 ways as a sum of consecutive naturals, for example, 7882916670 + ... + 7882919368.

Almost surely, 2^{21275995733281} is an apocalyptic number.

21275995733281 is the 4612591-st square number.

21275995733281 is the 2306296-th centered octagonal number.

It is an amenable number.

21275995733281 is a deficient number, since it is larger than the sum of its proper divisors (20347123410).

21275995733281 is an frugal number, since it uses more digits than its factorization.

21275995733281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8816 (or 4408 counting only the distinct ones).

The product of its digits is 57153600, while the sum is 64.

The spelling of 21275995733281 in words is "twenty-one trillion, two hundred seventy-five billion, nine hundred ninety-five million, seven hundred thirty-three thousand, two hundred eighty-one".