21652140 has 24 divisors (see below), whose sum is σ = 60626160. Its totient is φ = 5773888.

The previous prime is 21652121. The next prime is 21652159. The reversal of 21652140 is 4125612.

It is an interprime number because it is at equal distance from previous prime (21652121) and next prime (21652159).

It is a zygodrome in base 9.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180375 + ... + 180494.

It is an arithmetic number, because the mean of its divisors is an integer number (2526090).

Almost surely, 2^21652140 is an apocalyptic number.

21652140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21652140 is an abundant number, since it is smaller than the sum of its proper divisors (38974020).

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

21652140 is a wasteful number, since it uses less digits than its factorization.

21652140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360881 (or 360879 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 21652140 is about 4653.1860053086. The cubic root of 21652140 is about 278.7192355465.

Adding to 21652140 its reverse (4125612), we get a palindrome (25777752).

The spelling of 21652140 in words is "twenty-one million, six hundred fifty-two thousand, one hundred forty".