21446156281 has 12 divisors (see below), whose sum is σ = 23806457892. Its totient is φ = 19303460000.

The previous prime is 21446156177. The next prime is 21446156287. The reversal of 21446156281 is 18265164412.

It can be written as a sum of positive squares in 2 ways, for example, as 11904773881 + 9541382400 = 109109^2 + 97680^2 .

It is not a de Polignac number, because 21446156281 - 2⁹ = 21446155769 is a prime.

It is a super-2 number, since 2×21446156281² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21446156287) 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 11 ways as a sum of consecutive naturals, for example, 865210 + ... + 889651.

It is an arithmetic number, because the mean of its divisors is an integer number (1983871491).

Almost surely, 2^21446156281 is an apocalyptic number.

It is an amenable number.

21446156281 is a deficient number, since it is larger than the sum of its proper divisors (2360301611).

21446156281 is a wasteful number, since it uses less digits than its factorization.

21446156281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1754984 (or 1754973 counting only the distinct ones).

The product of its digits is 92160, while the sum is 40.

The spelling of 21446156281 in words is "twenty-one billion, four hundred forty-six million, one hundred fifty-six thousand, two hundred eighty-one".