138958881 has 8 divisors (see below), whose sum is σ = 189797664. Its totient is φ = 90379680.

The previous prime is 138958879. The next prime is 138958927. The reversal of 138958881 is 188859831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138958881 - 2¹ = 138958879 is a prime.

It is a super-2 number, since 2×138958881² = 38619141217544322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138958811) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 564751 + ... + 564996.

It is an arithmetic number, because the mean of its divisors is an integer number (23724708).

Almost surely, 2^138958881 is an apocalyptic number.

It is an amenable number.

138958881 is a deficient number, since it is larger than the sum of its proper divisors (50838783).

138958881 is a wasteful number, since it uses less digits than its factorization.

138958881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1129791.

The product of its digits is 552960, while the sum is 51.

The square root of 138958881 is about 11788.0821595372. The cubic root of 138958881 is about 517.9590624217.

The spelling of 138958881 in words is "one hundred thirty-eight million, nine hundred fifty-eight thousand, eight hundred eighty-one".