138446643 has 4 divisors (see below), whose sum is σ = 184595528. Its totient is φ = 92297760.

The previous prime is 138446639. The next prime is 138446669. The reversal of 138446643 is 346644831.

It is a happy number.

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

It is not a de Polignac number, because 138446643 - 2² = 138446639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138446543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23074438 + ... + 23074443.

It is an arithmetic number, because the mean of its divisors is an integer number (46148882).

Almost surely, 2^138446643 is an apocalyptic number.

138446643 is a deficient number, since it is larger than the sum of its proper divisors (46148885).

138446643 is an equidigital number, since it uses as much as digits as its factorization.

138446643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46148884.

The product of its digits is 165888, while the sum is 39.

The square root of 138446643 is about 11766.3351558589. The cubic root of 138446643 is about 517.3218355625.

The spelling of 138446643 in words is "one hundred thirty-eight million, four hundred forty-six thousand, six hundred forty-three".