21035953 has 8 divisors (see below), whose sum is σ = 22337640. Its totient is φ = 19741440.

The previous prime is 21035929. The next prime is 21035981. The reversal of 21035953 is 35953012.

It can be written as a sum of positive squares in 4 ways, for example, as 451584 + 20584369 = 672^2 + 4537^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21035953 - 2⁵ = 21035921 is a prime.

It is a super-2 number, since 2×21035953² = 885022637236418, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21030953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5023 + ... + 8203.

It is an arithmetic number, because the mean of its divisors is an integer number (2792205).

Almost surely, 2^21035953 is an apocalyptic number.

It is an amenable number.

21035953 is a deficient number, since it is larger than the sum of its proper divisors (1301687).

21035953 is a wasteful number, since it uses less digits than its factorization.

21035953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3587.

The product of its (nonzero) digits is 4050, while the sum is 28.

The square root of 21035953 is about 4586.4968112929. The cubic root of 21035953 is about 276.0497748568.

Adding to 21035953 its reverse (35953012), we get a palindrome (56988965).

It can be divided in two parts, 210 and 35953, that added together give a palindrome (36163).

The spelling of 21035953 in words is "twenty-one million, thirty-five thousand, nine hundred fifty-three".