138547631 has 4 divisors (see below), whose sum is σ = 138696432. Its totient is φ = 138398832.

The previous prime is 138547627. The next prime is 138547679. The reversal of 138547631 is 136745831.

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

It is a cyclic number.

It is not a de Polignac number, because 138547631 - 2² = 138547627 is a prime.

It is a super-2 number, since 2×138547631² = 38390892111424322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138547621) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 72995 + ... + 74868.

It is an arithmetic number, because the mean of its divisors is an integer number (34674108).

Almost surely, 2^138547631 is an apocalyptic number.

138547631 is a deficient number, since it is larger than the sum of its proper divisors (148801).

138547631 is an equidigital number, since it uses as much as digits as its factorization.

138547631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148800.

The product of its digits is 60480, while the sum is 38.

The square root of 138547631 is about 11770.6257692614. The cubic root of 138547631 is about 517.4475894241.

The spelling of 138547631 in words is "one hundred thirty-eight million, five hundred forty-seven thousand, six hundred thirty-one".