21733513 has 2 divisors, whose sum is σ = 21733514. Its totient is φ = 21733512.

The previous prime is 21733477. The next prime is 21733561. The reversal of 21733513 is 31533712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21233664 + 499849 = 4608^2 + 707^2 .

It is a cyclic number.

It is not a de Polignac number, because 21733513 - 2⁹ = 21733001 is a prime.

It is not a weakly prime, because it can be changed into another prime (21733013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10866756 + 10866757.

It is an arithmetic number, because the mean of its divisors is an integer number (10866757).

Almost surely, 2^21733513 is an apocalyptic number.

It is an amenable number.

21733513 is a deficient number, since it is larger than the sum of its proper divisors (1).

21733513 is an equidigital number, since it uses as much as digits as its factorization.

21733513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1890, while the sum is 25.

The square root of 21733513 is about 4661.9215995124. The cubic root of 21733513 is about 279.0679596185.

The spelling of 21733513 in words is "twenty-one million, seven hundred thirty-three thousand, five hundred thirteen".