138021000 has 128 divisors (see below), whose sum is σ = 463881600. Its totient is φ = 33964800.

The previous prime is 138020969. The next prime is 138021017. The reversal of 138021000 is 120831.

It is a happy number.

138021000 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37231 + ... + 40769.

It is an arithmetic number, because the mean of its divisors is an integer number (3624075).

Almost surely, 2^138021000 is an apocalyptic number.

138021000 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 138021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (231940800).

138021000 is an abundant number, since it is smaller than the sum of its proper divisors (325860600).

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

138021000 is a wasteful number, since it uses less digits than its factorization.

138021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3576 (or 3562 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 138021000 is about 11748.2339098266. The cubic root of 138021000 is about 516.7911366204.

Adding to 138021000 its reverse (120831), we get a palindrome (138141831).

The spelling of 138021000 in words is "one hundred thirty-eight million, twenty-one thousand".