138883021 has 4 divisors (see below), whose sum is σ = 138953500. Its totient is φ = 138812544.

The previous prime is 138882983. The next prime is 138883033. The reversal of 138883021 is 120388831.

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

It can be written as a sum of positive squares in 2 ways, for example, as 80910025 + 57972996 = 8995^2 + 7614^2 .

It is a cyclic number.

It is not a de Polignac number, because 138883021 - 2¹⁵ = 138850253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138883061) 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, 32196 + ... + 36253.

It is an arithmetic number, because the mean of its divisors is an integer number (34738375).

Almost surely, 2^138883021 is an apocalyptic number.

It is an amenable number.

138883021 is a deficient number, since it is larger than the sum of its proper divisors (70479).

138883021 is an equidigital number, since it uses as much as digits as its factorization.

138883021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70478.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 138883021 is about 11784.8640637048. The cubic root of 138883021 is about 517.8647910649.

The spelling of 138883021 in words is "one hundred thirty-eight million, eight hundred eighty-three thousand, twenty-one".