138549998 has 4 divisors (see below), whose sum is σ = 207825000. Its totient is φ = 69274998.

The previous prime is 138549997. The next prime is 138550007. The reversal of 138549998 is 899945831.

138549998 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a super-2 number, since 2×138549998² = 38392203891600008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138549997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34637498 + ... + 34637501.

It is an arithmetic number, because the mean of its divisors is an integer number (51956250).

Almost surely, 2^138549998 is an apocalyptic number.

138549998 is a deficient number, since it is larger than the sum of its proper divisors (69275002).

138549998 is an equidigital number, since it uses as much as digits as its factorization.

138549998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69275001.

The product of its digits is 2799360, while the sum is 56.

The square root of 138549998 is about 11770.7263157377. The cubic root of 138549998 is about 517.4505361639.

The spelling of 138549998 in words is "one hundred thirty-eight million, five hundred forty-nine thousand, nine hundred ninety-eight".