138976506 has 64 divisors (see below), whose sum is σ = 317116800. Its totient is φ = 45100800.

The previous prime is 138976471. The next prime is 138976567. The reversal of 138976506 is 605679831.

It is a happy number.

138976506 is a `hidden beast` number, since 138 + 9 + 7 + 6 + 506 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 576546 + ... + 576786.

It is an arithmetic number, because the mean of its divisors is an integer number (4954950).

Almost surely, 2^138976506 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138976506, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158558400).

138976506 is an abundant number, since it is smaller than the sum of its proper divisors (178140294).

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

138976506 is a wasteful number, since it uses less digits than its factorization.

138976506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492 (or 486 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 138976506 is about 11788.8297129104. The cubic root of 138976506 is about 517.9809601286.

The spelling of 138976506 in words is "one hundred thirty-eight million, nine hundred seventy-six thousand, five hundred six".