21317032 has 32 divisors (see below), whose sum is σ = 44788320. Its totient is φ = 9426240.

The previous prime is 21317029. The next prime is 21317033. The reversal of 21317032 is 23071312.

It is not an unprimeable number, because it can be changed into a prime (21317033) 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, 18 + ... + 6529.

It is an arithmetic number, because the mean of its divisors is an integer number (1399635).

Almost surely, 2^21317032 is an apocalyptic number.

21317032 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21317032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22394160).

21317032 is an abundant number, since it is smaller than the sum of its proper divisors (23471288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21317032 is a wasteful number, since it uses less digits than its factorization.

21317032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6601 (or 6597 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 21317032 is about 4617.0371451830. The cubic root of 21317032 is about 277.2738497817.

Adding to 21317032 its reverse (23071312), we get a palindrome (44388344).

The spelling of 21317032 in words is "twenty-one million, three hundred seventeen thousand, thirty-two".