21329413 has 8 divisors (see below), whose sum is σ = 25217280. Its totient is φ = 17651760.

The previous prime is 21329401. The next prime is 21329431. The reversal of 21329413 is 31492312.

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

It is a de Polignac number, because none of the positive numbers 2^k-21329413 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 (21329513) 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, 52333 + ... + 52738.

It is an arithmetic number, because the mean of its divisors is an integer number (3152160).

Almost surely, 2^21329413 is an apocalyptic number.

It is an amenable number.

21329413 is a deficient number, since it is larger than the sum of its proper divisors (3887867).

21329413 is a wasteful number, since it uses less digits than its factorization.

21329413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105107.

The product of its digits is 1296, while the sum is 25.

The square root of 21329413 is about 4618.3777454860. The cubic root of 21329413 is about 277.3275199038.

The spelling of 21329413 in words is "twenty-one million, three hundred twenty-nine thousand, four hundred thirteen".