21136735 has 8 divisors (see below), whose sum is σ = 25597440. Its totient is φ = 16753824.

The previous prime is 21136723. The next prime is 21136751. The reversal of 21136735 is 53763112.

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 21136735 - 2¹³ = 21128543 is a prime.

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, 18847 + ... + 19936.

It is an arithmetic number, because the mean of its divisors is an integer number (3199680).

Almost surely, 2^21136735 is an apocalyptic number.

21136735 is a deficient number, since it is larger than the sum of its proper divisors (4460705).

21136735 is a wasteful number, since it uses less digits than its factorization.

21136735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38897.

The product of its digits is 3780, while the sum is 28.

The square root of 21136735 is about 4597.4705001772. The cubic root of 21136735 is about 276.4899187214.

Adding to 21136735 its reverse (53763112), we get a palindrome (74899847).

The spelling of 21136735 in words is "twenty-one million, one hundred thirty-six thousand, seven hundred thirty-five".