20851632 has 60 divisors (see below), whose sum is σ = 59047560. Its totient is φ = 6868224.

The previous prime is 20851601. The next prime is 20851637. The reversal of 20851632 is 23615802.

20851632 is a `hidden beast` number, since 20 + 8 + 5 + 1 + 632 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 20851596 and 20851605.

It is not an unprimeable number, because it can be changed into a prime (20851637) 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 11 ways as a sum of consecutive naturals, for example, 12003 + ... + 13629.

It is an arithmetic number, because the mean of its divisors is an integer number (984126).

Almost surely, 2^20851632 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 20851632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29523780).

20851632 is an abundant number, since it is smaller than the sum of its proper divisors (38195928).

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

20851632 is a wasteful number, since it uses less digits than its factorization.

20851632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1730 (or 1721 counting only the distinct ones).

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

The square root of 20851632 is about 4566.3587244105. The cubic root of 20851632 is about 275.2411416542.

The spelling of 20851632 in words is "twenty million, eight hundred fifty-one thousand, six hundred thirty-two".