138780634 has 4 divisors (see below), whose sum is σ = 208170954. Its totient is φ = 69390316.

The previous prime is 138780559. The next prime is 138780671. The reversal of 138780634 is 436087831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 82755409 + 56025225 = 9097^2 + 7485^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34695157 + ... + 34695160.

Almost surely, 2^138780634 is an apocalyptic number.

138780634 is a deficient number, since it is larger than the sum of its proper divisors (69390320).

138780634 is an equidigital number, since it uses as much as digits as its factorization.

138780634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69390319.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 138780634 is about 11780.5192585047. The cubic root of 138780634 is about 517.7375001092.

The spelling of 138780634 in words is "one hundred thirty-eight million, seven hundred eighty thousand, six hundred thirty-four".