21345852 has 72 divisors (see below), whose sum is σ = 55874896. Its totient is φ = 6336000.

The previous prime is 21345851. The next prime is 21345853. The reversal of 21345852 is 25854312.

It is an interprime number because it is at equal distance from previous prime (21345851) and next prime (21345853).

It is a super-3 number, since 3×21345852³ (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 (21345851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 88452 + ... + 88692.

Almost surely, 2^21345852 is an apocalyptic number.

21345852 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 21345852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27937448).

21345852 is an abundant number, since it is smaller than the sum of its proper divisors (34529044).

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

21345852 is a wasteful number, since it uses less digits than its factorization.

21345852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331 (or 318 counting only the distinct ones).

The product of its digits is 9600, while the sum is 30.

The square root of 21345852 is about 4620.1571401847. The cubic root of 21345852 is about 277.3987488739.

The spelling of 21345852 in words is "twenty-one million, three hundred forty-five thousand, eight hundred fifty-two".