20638332 has 144 divisors (see below), whose sum is σ = 64821120. Its totient is φ = 5443200.

The previous prime is 20638309. The next prime is 20638339. The reversal of 20638332 is 23383602.

20638332 is a `hidden beast` number, since 20 + 638 + 3 + 3 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 20638296 and 20638305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20638339) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 97707 + ... + 97917.

Almost surely, 2^20638332 is an apocalyptic number.

20638332 is a gapful number since it is divisible by the number (22) 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 20638332, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32410560).

20638332 is an abundant number, since it is smaller than the sum of its proper divisors (44182788).

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

20638332 is a wasteful number, since it uses less digits than its factorization.

20638332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 20638332 is about 4542.9430989173. The cubic root of 20638332 is about 274.2994045436.

The spelling of 20638332 in words is "twenty million, six hundred thirty-eight thousand, three hundred thirty-two".