138355751 has 4 divisors (see below), whose sum is σ = 139910400. Its totient is φ = 136801104.

The previous prime is 138355729. The next prime is 138355793. The reversal of 138355751 is 157553831.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138355751 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 (138351751) 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, 777191 + ... + 777368.

It is an arithmetic number, because the mean of its divisors is an integer number (34977600).

Almost surely, 2^138355751 is an apocalyptic number.

138355751 is a deficient number, since it is larger than the sum of its proper divisors (1554649).

138355751 is an equidigital number, since it uses as much as digits as its factorization.

138355751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1554648.

The product of its digits is 63000, while the sum is 38.

The square root of 138355751 is about 11762.4721466195. The cubic root of 138355751 is about 517.2086013016.

The spelling of 138355751 in words is "one hundred thirty-eight million, three hundred fifty-five thousand, seven hundred fifty-one".