20603538 has 64 divisors (see below), whose sum is σ = 48833280. Its totient is φ = 6424704.

The previous prime is 20603533. The next prime is 20603563. The reversal of 20603538 is 83530602.

20603538 is a `hidden beast` number, since 2 + 0 + 603 + 53 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20603533) 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 31 ways as a sum of consecutive naturals, for example, 65670 + ... + 65982.

It is an arithmetic number, because the mean of its divisors is an integer number (763020).

Almost surely, 2^20603538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20603538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24416640).

20603538 is an abundant number, since it is smaller than the sum of its proper divisors (28229742).

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

20603538 is a wasteful number, since it uses less digits than its factorization.

20603538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400 (or 394 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20603538 is about 4539.1120276988. The cubic root of 20603538 is about 274.1451714418.

The spelling of 20603538 in words is "twenty million, six hundred three thousand, five hundred thirty-eight".