21727513 has 8 divisors (see below), whose sum is σ = 23541408. Its totient is φ = 19973184.

The previous prime is 21727493. The next prime is 21727543. The reversal of 21727513 is 31572712.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21727513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21727543) 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, 14131 + ... + 15592.

It is an arithmetic number, because the mean of its divisors is an integer number (2942676).

Almost surely, 2^21727513 is an apocalyptic number.

It is an amenable number.

21727513 is a deficient number, since it is larger than the sum of its proper divisors (1813895).

21727513 is a wasteful number, since it uses less digits than its factorization.

21727513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29783.

The product of its digits is 2940, while the sum is 28.

The square root of 21727513 is about 4661.2780436271. The cubic root of 21727513 is about 279.0422763666.

It can be divided in two parts, 217 and 27513, that added together give a triangular number (27730 = T₂₃₅).

The spelling of 21727513 in words is "twenty-one million, seven hundred twenty-seven thousand, five hundred thirteen".