21432017 has 8 divisors (see below), whose sum is σ = 21995424. Its totient is φ = 20871648.

The previous prime is 21432013. The next prime is 21432023. The reversal of 21432017 is 71023412.

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 21432017 - 2² = 21432013 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21432017.

It is not an unprimeable number, because it can be changed into a prime (21432013) 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, 22013 + ... + 22965.

It is an arithmetic number, because the mean of its divisors is an integer number (2749428).

Almost surely, 2^21432017 is an apocalyptic number.

It is an amenable number.

21432017 is a deficient number, since it is larger than the sum of its proper divisors (563407).

21432017 is an equidigital number, since it uses as much as digits as its factorization.

21432017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1519.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21432017 is about 4629.4726481534. The cubic root of 21432017 is about 277.7714984832.

Adding to 21432017 its reverse (71023412), we get a palindrome (92455429).

The spelling of 21432017 in words is "twenty-one million, four hundred thirty-two thousand, seventeen".