138891980 has 12 divisors (see below), whose sum is σ = 291673200. Its totient is φ = 55556784.

The previous prime is 138891967. The next prime is 138891983. The reversal of 138891980 is 89198831.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (138891983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3472280 + ... + 3472319.

It is an arithmetic number, because the mean of its divisors is an integer number (24306100).

Almost surely, 2^138891980 is an apocalyptic number.

138891980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138891980 is an abundant number, since it is smaller than the sum of its proper divisors (152781220).

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

138891980 is a wasteful number, since it uses less digits than its factorization.

138891980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6944608 (or 6944606 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 47.

The square root of 138891980 is about 11785.2441637838. The cubic root of 138891980 is about 517.8759262175.

The spelling of 138891980 in words is "one hundred thirty-eight million, eight hundred ninety-one thousand, nine hundred eighty".