21650328 has 192 divisors, whose sum is σ = 73032960. Its totient is φ = 5878656.

The previous prime is 21650297. The next prime is 21650339. The reversal of 21650328 is 82305612.

21650328 is a `hidden beast` number, since 2 + 1 + 650 + 3 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 503475 + ... + 503517.

It is an arithmetic number, because the mean of its divisors is an integer number (380380).

Almost surely, 2^21650328 is an apocalyptic number.

21650328 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 21650328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36516480).

21650328 is an abundant number, since it is smaller than the sum of its proper divisors (51382632).

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

21650328 is a wasteful number, since it uses less digits than its factorization.

21650328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 92 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 21650328 is about 4652.9912959300. The cubic root of 21650328 is about 278.7114602821.

The spelling of 21650328 in words is "twenty-one million, six hundred fifty thousand, three hundred twenty-eight".