21136535 has 8 divisors (see below), whose sum is σ = 28987296. Its totient is φ = 14493600.

The previous prime is 21136523. The next prime is 21136541. The reversal of 21136535 is 53563112.

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

It is not a de Polignac number, because 21136535 - 2⁴ = 21136519 is a prime.

It is a super-2 number, since 2×21136535² = 893506223612450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 301916 + ... + 301985.

It is an arithmetic number, because the mean of its divisors is an integer number (3623412).

Almost surely, 2^21136535 is an apocalyptic number.

21136535 is a deficient number, since it is larger than the sum of its proper divisors (7850761).

21136535 is an equidigital number, since it uses as much as digits as its factorization.

21136535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 603913.

The product of its digits is 2700, while the sum is 26.

The square root of 21136535 is about 4597.4487490346. The cubic root of 21136535 is about 276.4890466510.

Adding to 21136535 its reverse (53563112), we get a palindrome (74699647).

The spelling of 21136535 in words is "twenty-one million, one hundred thirty-six thousand, five hundred thirty-five".