21317153 has 12 divisors (see below), whose sum is σ = 25183728. Its totient is φ = 17886960.

The previous prime is 21317147. The next prime is 21317209. The reversal of 21317153 is 35171312.

It is not a de Polignac number, because 21317153 - 2¹⁶ = 21251617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21316153) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3875 + ... + 7592.

It is an arithmetic number, because the mean of its divisors is an integer number (2098644).

Almost surely, 2^21317153 is an apocalyptic number.

It is an amenable number.

21317153 is a deficient number, since it is larger than the sum of its proper divisors (3866575).

21317153 is a wasteful number, since it uses less digits than its factorization.

21317153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11504 (or 11491 counting only the distinct ones).

The product of its digits is 630, while the sum is 23.

The square root of 21317153 is about 4617.0502488060. The cubic root of 21317153 is about 277.2743744024.

Adding to 21317153 its reverse (35171312), we get a palindrome (56488465).

The spelling of 21317153 in words is "twenty-one million, three hundred seventeen thousand, one hundred fifty-three".