21540848 has 40 divisors (see below), whose sum is σ = 48255840. Its totient is φ = 9123840.

The previous prime is 21540847. The next prime is 21540859. The reversal of 21540848 is 84804512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540847) 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 7 ways as a sum of consecutive naturals, for example, 8888 + ... + 11048.

It is an arithmetic number, because the mean of its divisors is an integer number (1206396).

Almost surely, 2^21540848 is an apocalyptic number.

21540848 is a gapful number since it is divisible by the number (28) 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 21540848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24127920).

21540848 is an abundant number, since it is smaller than the sum of its proper divisors (26714992).

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

21540848 is a wasteful number, since it uses less digits than its factorization.

21540848 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2265 (or 2259 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 32.

The square root of 21540848 is about 4641.2119106975. The cubic root of 21540848 is about 278.2408760601.

The spelling of 21540848 in words is "twenty-one million, five hundred forty thousand, eight hundred forty-eight".