21500753 has 2 divisors, whose sum is σ = 21500754. Its totient is φ = 21500752.

The previous prime is 21500747. The next prime is 21500783. The reversal of 21500753 is 35700512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21418384 + 82369 = 4628^2 + 287^2 .

It is a cyclic number.

It is not a de Polignac number, because 21500753 - 2⁸ = 21500497 is a prime.

It is a super-3 number, since 3×21500753³ (a number of 23 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21500783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750376 + 10750377.

It is an arithmetic number, because the mean of its divisors is an integer number (10750377).

Almost surely, 2^21500753 is an apocalyptic number.

It is an amenable number.

21500753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21500753 is an equidigital number, since it uses as much as digits as its factorization.

21500753 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1050, while the sum is 23.

The square root of 21500753 is about 4636.8904451151. The cubic root of 21500753 is about 278.0681345341.

The spelling of 21500753 in words is "twenty-one million, five hundred thousand, seven hundred fifty-three".