21845632 has 16 divisors (see below), whose sum is σ = 43520850. Its totient is φ = 10922752.

The previous prime is 21845627. The next prime is 21845689. The reversal of 21845632 is 23654812.

It can be written as a sum of positive squares in only one way, i.e., 11451456 + 10394176 = 3384^2 + 3224^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21845594 and 21845603.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85207 + ... + 85462.

Almost surely, 2^21845632 is an apocalyptic number.

It is an amenable number.

21845632 is a deficient number, since it is larger than the sum of its proper divisors (21675218).

21845632 is an equidigital number, since it uses as much as digits as its factorization.

21845632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170683 (or 170671 counting only the distinct ones).

The product of its digits is 11520, while the sum is 31.

The square root of 21845632 is about 4673.9311077507. The cubic root of 21845632 is about 279.5470226813.

The spelling of 21845632 in words is "twenty-one million, eight hundred forty-five thousand, six hundred thirty-two".