21363888 has 160 divisors (see below), whose sum is σ = 69884416. Its totient is φ = 5474304.

The previous prime is 21363887. The next prime is 21363899. The reversal of 21363888 is 88836312.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21363887) 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 31 ways as a sum of consecutive naturals, for example, 292620 + ... + 292692.

Almost surely, 2^21363888 is an apocalyptic number.

21363888 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 21363888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34942208).

21363888 is an abundant number, since it is smaller than the sum of its proper divisors (48520528).

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

21363888 is a wasteful number, since it uses less digits than its factorization.

21363888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171 (or 165 counting only the distinct ones).

The product of its digits is 55296, while the sum is 39.

The square root of 21363888 is about 4622.1086097148. The cubic root of 21363888 is about 277.4768554677.

The spelling of 21363888 in words is "twenty-one million, three hundred sixty-three thousand, eight hundred eighty-eight".