21237353 has 2 divisors, whose sum is σ = 21237354. Its totient is φ = 21237352.

The previous prime is 21237343. The next prime is 21237389. The reversal of 21237353 is 35373212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13017664 + 8219689 = 3608^2 + 2867^2 .

It is a cyclic number.

It is not a de Polignac number, because 21237353 - 2⁶ = 21237289 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21237323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10618676 + 10618677.

It is an arithmetic number, because the mean of its divisors is an integer number (10618677).

Almost surely, 2^21237353 is an apocalyptic number.

It is an amenable number.

21237353 is a deficient number, since it is larger than the sum of its proper divisors (1).

21237353 is an equidigital number, since it uses as much as digits as its factorization.

21237353 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780, while the sum is 26.

The square root of 21237353 is about 4608.4002647340. The cubic root of 21237353 is about 276.9279528680.

The spelling of 21237353 in words is "twenty-one million, two hundred thirty-seven thousand, three hundred fifty-three".