21529117 has 8 divisors (see below), whose sum is σ = 21919680. Its totient is φ = 21141120.

The previous prime is 21529093. The next prime is 21529129. The reversal of 21529117 is 71192512.

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 21529117 - 2¹⁹ = 21004829 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 (21529217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24634 + ... + 25492.

It is an arithmetic number, because the mean of its divisors is an integer number (2739960).

Almost surely, 2^21529117 is an apocalyptic number.

It is an amenable number.

21529117 is a deficient number, since it is larger than the sum of its proper divisors (390563).

21529117 is an equidigital number, since it uses as much as digits as its factorization.

21529117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1283.

The product of its digits is 1260, while the sum is 28.

The square root of 21529117 is about 4639.9479522943. The cubic root of 21529117 is about 278.1903575224.

The spelling of 21529117 in words is "twenty-one million, five hundred twenty-nine thousand, one hundred seventeen".