21254733 has 6 divisors (see below), whose sum is σ = 30701294. Its totient is φ = 14169816.

The previous prime is 21254729. The next prime is 21254789. The reversal of 21254733 is 33745212.

It can be written as a sum of positive squares in only one way, i.e., 18688329 + 2566404 = 4323^2 + 1602^2 .

It is not a de Polignac number, because 21254733 - 2² = 21254729 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21254697 and 21254706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21254033) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1180810 + ... + 1180827.

Almost surely, 2^21254733 is an apocalyptic number.

It is an amenable number.

21254733 is a deficient number, since it is larger than the sum of its proper divisors (9446561).

21254733 is a wasteful number, since it uses less digits than its factorization.

21254733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2361643 (or 2361640 counting only the distinct ones).

The product of its digits is 5040, while the sum is 27.

The square root of 21254733 is about 4610.2855659926. The cubic root of 21254733 is about 277.0034753916.

Adding to 21254733 its reverse (33745212), we get a palindrome (54999945).

It can be divided in two parts, 212 and 54733, that added together give a palindrome (54945).

The spelling of 21254733 in words is "twenty-one million, two hundred fifty-four thousand, seven hundred thirty-three".