21052351 has 2 divisors, whose sum is σ = 21052352. Its totient is φ = 21052350.

The previous prime is 21052349. The next prime is 21052373. The reversal of 21052351 is 15325012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21052351 - 2¹ = 21052349 is a prime.

Together with 21052349, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21052301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10526175 + 10526176.

It is an arithmetic number, because the mean of its divisors is an integer number (10526176).

Almost surely, 2^21052351 is an apocalyptic number.

21052351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21052351 is an equidigital number, since it uses as much as digits as its factorization.

21052351 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 21052351 is about 4588.2841019274. The cubic root of 21052351 is about 276.1214852361.

Adding to 21052351 its reverse (15325012), we get a palindrome (36377363).

The spelling of 21052351 in words is "twenty-one million, fifty-two thousand, three hundred fifty-one".