21153882 has 64 divisors (see below), whose sum is σ = 47775744. Its totient is φ = 6209280.

The previous prime is 21153877. The next prime is 21153883. The reversal of 21153882 is 28835112.

It is not an unprimeable number, because it can be changed into a prime (21153883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 166503 + ... + 166629.

It is an arithmetic number, because the mean of its divisors is an integer number (746496).

Almost surely, 2^21153882 is an apocalyptic number.

21153882 is an abundant number, since it is smaller than the sum of its proper divisors (26621862).

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

21153882 is a wasteful number, since it uses less digits than its factorization.

21153882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243.

The product of its digits is 3840, while the sum is 30.

The square root of 21153882 is about 4599.3349519251. The cubic root of 21153882 is about 276.5646652261.

Adding to 21153882 its reverse (28835112), we get a palindrome (49988994).

The spelling of 21153882 in words is "twenty-one million, one hundred fifty-three thousand, eight hundred eighty-two".