138620020 has 144 divisors (see below), whose sum is σ = 375379200. Its totient is φ = 42947520.

The previous prime is 138619997. The next prime is 138620039. The reversal of 138620020 is 20026831.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 138619973 and 138620000.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 829977 + ... + 830143.

It is an arithmetic number, because the mean of its divisors is an integer number (2606800).

Almost surely, 2^138620020 is an apocalyptic number.

138620020 is a gapful number since it is divisible by the number (10) 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 138620020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187689600).

138620020 is an abundant number, since it is smaller than the sum of its proper divisors (236759180).

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

138620020 is a wasteful number, since it uses less digits than its factorization.

138620020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 138620020 is about 11773.7003529052. The cubic root of 138620020 is about 517.5376931945.

Adding to 138620020 its reverse (20026831), we get a palindrome (158646851).

The spelling of 138620020 in words is "one hundred thirty-eight million, six hundred twenty thousand, twenty".