138499020 has 108 divisors (see below), whose sum is σ = 461850480. Its totient is φ = 33570240.

The previous prime is 138498967. The next prime is 138499027. The reversal of 138499020 is 20994831.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (138499027) 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 35 ways as a sum of consecutive naturals, for example, 18601 + ... + 24959.

Almost surely, 2^138499020 is an apocalyptic number.

138499020 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 138499020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230925240).

138499020 is an abundant number, since it is smaller than the sum of its proper divisors (323351460).

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

138499020 is a wasteful number, since it uses less digits than its factorization.

138499020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6396 (or 6380 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 138499020 is about 11768.5606596559. The cubic root of 138499020 is about 517.3870649027.

The spelling of 138499020 in words is "one hundred thirty-eight million, four hundred ninety-nine thousand, twenty".