20025138 has 64 divisors (see below), whose sum is σ = 48625920. Its totient is φ = 5376000.

The previous prime is 20025127. The next prime is 20025139. The reversal of 20025138 is 83152002.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (20025139) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 49738 + ... + 50138.

It is an arithmetic number, because the mean of its divisors is an integer number (759780).

Almost surely, 2^20025138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20025138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24312960).

20025138 is an abundant number, since it is smaller than the sum of its proper divisors (28600782).

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

20025138 is a wasteful number, since it uses less digits than its factorization.

20025138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 483.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20025138 is about 4474.9455862614. The cubic root of 20025138 is about 271.5554390958. Note that the first 3 decimals are identical.

It can be divided in two parts, 2002 and 5138, that added together give a triangular number (7140 = T₁₁₉).

The spelling of 20025138 in words is "twenty million, twenty-five thousand, one hundred thirty-eight".