21235753 has 16 divisors (see below), whose sum is σ = 26818560. Its totient is φ = 16333200.

The previous prime is 21235741. The next prime is 21235759. The reversal of 21235753 is 35753212.

It is a cyclic number.

It is not a de Polignac number, because 21235753 - 2¹³ = 21227561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21235759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4338 + ... + 7828.

It is an arithmetic number, because the mean of its divisors is an integer number (1676160).

Almost surely, 2^21235753 is an apocalyptic number.

It is an amenable number.

21235753 is a deficient number, since it is larger than the sum of its proper divisors (5582807).

21235753 is a wasteful number, since it uses less digits than its factorization.

21235753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3588.

The product of its digits is 6300, while the sum is 28.

The square root of 21235753 is about 4608.2266654322. The cubic root of 21235753 is about 276.9209982057.

Adding to 21235753 its reverse (35753212), we get a palindrome (56988965).

The spelling of 21235753 in words is "twenty-one million, two hundred thirty-five thousand, seven hundred fifty-three".