138420900 has 180 divisors, whose sum is σ = 468844992. Its totient is φ = 35259840.

The previous prime is 138420889. The next prime is 138420911. The reversal of 138420900 is 9024831.

It is an interprime number because it is at equal distance from previous prime (138420889) and next prime (138420911).

It is a tau number, because it is divible by the number of its divisors (180).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 185929 + ... + 186671.

Almost surely, 2^138420900 is an apocalyptic number.

138420900 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 138420900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (234422496).

138420900 is an abundant number, since it is smaller than the sum of its proper divisors (330424092).

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

138420900 is a wasteful number, since it uses less digits than its factorization.

138420900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 792 (or 776 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 138420900 is about 11765.2411789984. The cubic root of 138420900 is about 517.2897696796.

The spelling of 138420900 in words is "one hundred thirty-eight million, four hundred twenty thousand, nine hundred".