21254241361 has 16 divisors (see below), whose sum is σ = 21956014080. Its totient is φ = 20564398800.

The previous prime is 21254241353. The next prime is 21254241391. The reversal of 21254241361 is 16314245212.

It is a cyclic number.

It is not a de Polignac number, because 21254241361 - 2³ = 21254241353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21254241341) 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, 9039336 + ... + 9041686.

It is an arithmetic number, because the mean of its divisors is an integer number (1372250880).

Almost surely, 2^21254241361 is an apocalyptic number.

It is an amenable number.

21254241361 is a deficient number, since it is larger than the sum of its proper divisors (701772719).

21254241361 is a wasteful number, since it uses less digits than its factorization.

21254241361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4764.

The product of its digits is 11520, while the sum is 31.

Adding to 21254241361 its reverse (16314245212), we get a palindrome (37568486573).

The spelling of 21254241361 in words is "twenty-one billion, two hundred fifty-four million, two hundred forty-one thousand, three hundred sixty-one".