21889648 has 40 divisors (see below), whose sum is σ = 46537200. Its totient is φ = 9891840.

The previous prime is 21889643. The next prime is 21889657. The reversal of 21889648 is 84698812.

It is a junction number, because it is equal to n+sod(n) for n = 21889598 and 21889607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21889643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48528 + ... + 48976.

It is an arithmetic number, because the mean of its divisors is an integer number (1163430).

Almost surely, 2^21889648 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 21889648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23268600).

21889648 is an abundant number, since it is smaller than the sum of its proper divisors (24647552).

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

21889648 is a wasteful number, since it uses less digits than its factorization.

21889648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745 (or 739 counting only the distinct ones).

The product of its digits is 221184, while the sum is 46.

The square root of 21889648 is about 4678.6374084770. The cubic root of 21889648 is about 279.7346465656.

The spelling of 21889648 in words is "twenty-one million, eight hundred eighty-nine thousand, six hundred forty-eight".