21136573 has 8 divisors (see below), whose sum is σ = 21713760. Its totient is φ = 20566800.

The previous prime is 21136571. The next prime is 21136579. The reversal of 21136573 is 37563112.

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 21136573 - 2¹ = 21136571 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21136571) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 4186 + ... + 7732.

It is an arithmetic number, because the mean of its divisors is an integer number (2714220).

Almost surely, 2^21136573 is an apocalyptic number.

It is an amenable number.

21136573 is a deficient number, since it is larger than the sum of its proper divisors (577187).

21136573 is a wasteful number, since it uses less digits than its factorization.

21136573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3707.

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

The square root of 21136573 is about 4597.4528817596. The cubic root of 21136573 is about 276.4892123448.

Adding to 21136573 its reverse (37563112), we get a palindrome (58699685).

The spelling of 21136573 in words is "twenty-one million, one hundred thirty-six thousand, five hundred seventy-three".