21054533 has 2 divisors, whose sum is σ = 21054534. Its totient is φ = 21054532.

The previous prime is 21054521. The next prime is 21054541. The reversal of 21054533 is 33545012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12096484 + 8958049 = 3478^2 + 2993^2 .

It is a cyclic number.

It is not a de Polignac number, because 21054533 - 2⁸ = 21054277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21054499 and 21054508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21054233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10527266 + 10527267.

It is an arithmetic number, because the mean of its divisors is an integer number (10527267).

Almost surely, 2^21054533 is an apocalyptic number.

It is an amenable number.

21054533 is a deficient number, since it is larger than the sum of its proper divisors (1).

21054533 is an equidigital number, since it uses as much as digits as its factorization.

21054533 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 21054533 is about 4588.5218752884. The cubic root of 21054533 is about 276.1310245708.

Adding to 21054533 its reverse (33545012), we get a palindrome (54599545).

The spelling of 21054533 in words is "twenty-one million, fifty-four thousand, five hundred thirty-three".