21535632 has 120 divisors (see below), whose sum is σ = 64995840. Its totient is φ = 6894720.

The previous prime is 21535621. The next prime is 21535639. The reversal of 21535632 is 23653512.

21535632 is a `hidden beast` number, since 21 + 5 + 3 + 5 + 632 = 666.

It is a hoax number, since the sum of its digits (27) 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 (27).

Its product of digits (5400) is a multiple of the sum of its prime divisors (225).

It is a junction number, because it is equal to n+sod(n) for n = 21535596 and 21535605.

It is not an unprimeable number, because it can be changed into a prime (21535639) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 112657 + ... + 112847.

It is an arithmetic number, because the mean of its divisors is an integer number (541632).

Almost surely, 2^21535632 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 21535632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32497920).

21535632 is an abundant number, since it is smaller than the sum of its proper divisors (43460208).

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

21535632 is a wasteful number, since it uses less digits than its factorization.

21535632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243 (or 225 counting only the distinct ones).

The product of its digits is 5400, while the sum is 27.

The square root of 21535632 is about 4640.6499544784. The cubic root of 21535632 is about 278.2184160720.

The spelling of 21535632 in words is "twenty-one million, five hundred thirty-five thousand, six hundred thirty-two".