21152663 has 18 divisors (see below), whose sum is σ = 25864776. Its totient is φ = 17215968.

The previous prime is 21152657. The next prime is 21152669. The reversal of 21152663 is 36625112.

It is an interprime number because it is at equal distance from previous prime (21152657) and next prime (21152669).

It is not a de Polignac number, because 21152663 - 2¹⁰ = 21151639 is a prime.

It is a super-3 number, since 3×21152663³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21152669) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 154331 + ... + 154467.

It is an arithmetic number, because the mean of its divisors is an integer number (1436932).

Almost surely, 2^21152663 is an apocalyptic number.

21152663 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21152663 is a deficient number, since it is larger than the sum of its proper divisors (4712113).

21152663 is an equidigital number, since it uses as much as digits as its factorization.

21152663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311 (or 167 counting only the distinct ones).

The product of its digits is 2160, while the sum is 26.

The square root of 21152663 is about 4599.2024308569. The cubic root of 21152663 is about 276.5593527449.

Adding to 21152663 its reverse (36625112), we get a palindrome (57777775).

The spelling of 21152663 in words is "twenty-one million, one hundred fifty-two thousand, six hundred sixty-three".