138973926 has 64 divisors (see below), whose sum is σ = 343526400. Its totient is φ = 36498816.

The previous prime is 138973903. The next prime is 138973943. The reversal of 138973926 is 629379831.

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 31 ways as a sum of consecutive naturals, for example, 195660 + ... + 196368.

It is an arithmetic number, because the mean of its divisors is an integer number (5367600).

Almost surely, 2^138973926 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138973926, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171763200).

138973926 is an abundant number, since it is smaller than the sum of its proper divisors (204552474).

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

138973926 is a wasteful number, since it uses less digits than its factorization.

138973926 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093.

The product of its digits is 489888, while the sum is 48.

The square root of 138973926 is about 11788.7202867826. The cubic root of 138973926 is about 517.9777547927.

The spelling of 138973926 in words is "one hundred thirty-eight million, nine hundred seventy-three thousand, nine hundred twenty-six".