138423852 has 72 divisors (see below), whose sum is σ = 401296896. Its totient is φ = 39410784.

The previous prime is 138423851. The next prime is 138423881. The reversal of 138423852 is 258324831.

It is a super-2 number, since 2×138423852² = 38322325605035808, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (138423851) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86653 + ... + 88235.

It is an arithmetic number, because the mean of its divisors is an integer number (5573568).

Almost surely, 2^138423852 is an apocalyptic number.

138423852 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138423852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200648448).

138423852 is an abundant number, since it is smaller than the sum of its proper divisors (262873044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138423852 is a wasteful number, since it uses less digits than its factorization.

138423852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1947 (or 1942 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 138423852 is about 11765.3666326214. The cubic root of 138423852 is about 517.2934469387.

The spelling of 138423852 in words is "one hundred thirty-eight million, four hundred twenty-three thousand, eight hundred fifty-two".