20523438 has 48 divisors (see below), whose sum is σ = 48222720. Its totient is φ = 6270912.

The previous prime is 20523431. The next prime is 20523449. The reversal of 20523438 is 83432502.

20523438 is a `hidden beast` number, since 205 + 23 + 438 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20523431) 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 23 ways as a sum of consecutive naturals, for example, 53395 + ... + 53777.

It is an arithmetic number, because the mean of its divisors is an integer number (1004640).

Almost surely, 2^20523438 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20523438, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24111360).

20523438 is an abundant number, since it is smaller than the sum of its proper divisors (27699282).

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

20523438 is a wasteful number, since it uses less digits than its factorization.

20523438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20523438 is about 4530.2801237893. The cubic root of 20523438 is about 273.7894469958.

The spelling of 20523438 in words is "twenty million, five hundred twenty-three thousand, four hundred thirty-eight".