21146832 has 210 divisors, whose sum is σ = 73390578. Its totient is φ = 5878656.

The previous prime is 21146831. The next prime is 21146833. The reversal of 21146832 is 23864112.

It is an interprime number because it is at equal distance from previous prime (21146831) and next prime (21146833).

It can be written as a sum of positive squares in only one way, i.e., 20575296 + 571536 = 4536^2 + 756^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21146796 and 21146805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21146831) by changing a digit.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 571518 + ... + 571554.

Almost surely, 2^21146832 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21146832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36695289).

21146832 is an abundant number, since it is smaller than the sum of its proper divisors (52243746).

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

21146832 is an equidigital number, since it uses as much as digits as its factorization.

21146832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 49 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21146832 is about 4598.5684729055. The cubic root of 21146832 is about 276.5339380443.

The spelling of 21146832 in words is "twenty-one million, one hundred forty-six thousand, eight hundred thirty-two".