21140535 has 16 divisors (see below), whose sum is σ = 36427104. Its totient is φ = 10407552.

The previous prime is 21140513. The next prime is 21140549. The reversal of 21140535 is 53504112.

It is not a de Polignac number, because 21140535 - 2¹⁸ = 20878391 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54012 + ... + 54401.

It is an arithmetic number, because the mean of its divisors is an integer number (2276694).

Almost surely, 2^21140535 is an apocalyptic number.

21140535 is a deficient number, since it is larger than the sum of its proper divisors (15286569).

21140535 is a wasteful number, since it uses less digits than its factorization.

21140535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108434.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21140535 is about 4597.8837523365. The cubic root of 21140535 is about 276.5064870125.

Adding to 21140535 its reverse (53504112), we get a palindrome (74644647).

It can be divided in two parts, 21 and 140535, that multiplied together give a triangular number (2951235 = T₂₄₂₉).

The spelling of 21140535 in words is "twenty-one million, one hundred forty thousand, five hundred thirty-five".