21040403533 has 2 divisors, whose sum is σ = 21040403534. Its totient is φ = 21040403532.

The previous prime is 21040403509. The next prime is 21040403557. The reversal of 21040403533 is 33530404012.

It is a balanced prime because it is at equal distance from previous prime (21040403509) and next prime (21040403557).

It can be written as a sum of positive squares in only one way, i.e., 20548362409 + 492041124 = 143347^2 + 22182^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21040403533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21040403498 and 21040403507.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21040403333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520201766 + 10520201767.

It is an arithmetic number, because the mean of its divisors is an integer number (10520201767).

Almost surely, 2^21040403533 is an apocalyptic number.

It is an amenable number.

21040403533 is a deficient number, since it is larger than the sum of its proper divisors (1).

21040403533 is an equidigital number, since it uses as much as digits as its factorization.

21040403533 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 25.

Adding to 21040403533 its reverse (33530404012), we get a palindrome (54570807545).

The spelling of 21040403533 in words is "twenty-one billion, forty million, four hundred three thousand, five hundred thirty-three".