20873538 has 80 divisors (see below), whose sum is σ = 54362880. Its totient is φ = 5863104.

The previous prime is 20873537. The next prime is 20873539. The reversal of 20873538 is 83537802.

It is an interprime number because it is at equal distance from previous prime (20873537) and next prime (20873539).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (20873537) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 89470 + ... + 89702.

It is an arithmetic number, because the mean of its divisors is an integer number (679536).

Almost surely, 2^20873538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20873538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27181440).

20873538 is an abundant number, since it is smaller than the sum of its proper divisors (33489342).

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

20873538 is a wasteful number, since it uses less digits than its factorization.

20873538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333 (or 324 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 20873538 is about 4568.7567236613. The cubic root of 20873538 is about 275.3374941802.

It can be divided in two parts, 2087 and 3538, that added together give a square (5625 = 75²).

The spelling of 20873538 in words is "twenty million, eight hundred seventy-three thousand, five hundred thirty-eight".