21552306281 has 16 divisors (see below), whose sum is σ = 23589273600. Its totient is φ = 19528381200.

The previous prime is 21552306253. The next prime is 21552306313. The reversal of 21552306281 is 18260325512.

It is a cyclic number.

It is not a de Polignac number, because 21552306281 - 2¹⁴ = 21552289897 is a prime.

It is a super-2 number, since 2×21552306281² (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 (21552306221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7484600 + ... + 7487478.

It is an arithmetic number, because the mean of its divisors is an integer number (1474329600).

Almost surely, 2^21552306281 is an apocalyptic number.

It is an amenable number.

21552306281 is a deficient number, since it is larger than the sum of its proper divisors (2036967319).

21552306281 is a wasteful number, since it uses less digits than its factorization.

21552306281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4900.

The product of its (nonzero) digits is 28800, while the sum is 35.

The spelling of 21552306281 in words is "twenty-one billion, five hundred fifty-two million, three hundred six thousand, two hundred eighty-one".