138727213 has 4 divisors (see below), whose sum is σ = 143510940. Its totient is φ = 133943488.

The previous prime is 138727207. The next prime is 138727217. The reversal of 138727213 is 312727831.

It is a happy number.

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 73650724 + 65076489 = 8582^2 + 8067^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138727213 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 (138727217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2391820 + ... + 2391877.

It is an arithmetic number, because the mean of its divisors is an integer number (35877735).

Almost surely, 2^138727213 is an apocalyptic number.

It is an amenable number.

138727213 is a deficient number, since it is larger than the sum of its proper divisors (4783727).

138727213 is an equidigital number, since it uses as much as digits as its factorization.

138727213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4783726.

The product of its digits is 14112, while the sum is 34.

The square root of 138727213 is about 11778.2516953918. The cubic root of 138727213 is about 517.6710604728.

The spelling of 138727213 in words is "one hundred thirty-eight million, seven hundred twenty-seven thousand, two hundred thirteen".