21601832 has 32 divisors (see below), whose sum is σ = 49014720. Its totient is φ = 8712960.

The previous prime is 21601831. The next prime is 21601843. The reversal of 21601832 is 23810612.

It is a junction number, because it is equal to n+sod(n) for n = 21601798 and 21601807.

It is not an unprimeable number, because it can be changed into a prime (21601831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10394 + ... + 12297.

It is an arithmetic number, because the mean of its divisors is an integer number (1531710).

Almost surely, 2^21601832 is an apocalyptic number.

It is an amenable number.

21601832 is an abundant number, since it is smaller than the sum of its proper divisors (27412888).

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

21601832 is a wasteful number, since it uses less digits than its factorization.

21601832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22721 (or 22717 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21601832 is about 4647.7771030892. Note that the first 3 decimals coincide. The cubic root of 21601832 is about 278.5032033041.

The spelling of 21601832 in words is "twenty-one million, six hundred one thousand, eight hundred thirty-two".