138249936 has 160 divisors (see below), whose sum is σ = 442828800. Its totient is φ = 40936320.

The previous prime is 138249913. The next prime is 138249971. The reversal of 138249936 is 639942831.

It is a happy number.

It is a super-2 number, since 2×138249936² = 38226089608008192, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 138249891 and 138249900.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 223035 + ... + 223653.

It is an arithmetic number, because the mean of its divisors is an integer number (2767680).

Almost surely, 2^138249936 is an apocalyptic number.

138249936 is a gapful number since it is divisible by the number (16) 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 138249936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221414400).

138249936 is an abundant number, since it is smaller than the sum of its proper divisors (304578864).

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

138249936 is a wasteful number, since it uses less digits than its factorization.

138249936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 694 (or 682 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 138249936 is about 11757.9732947477. The cubic root of 138249936 is about 517.0767133103.

The spelling of 138249936 in words is "one hundred thirty-eight million, two hundred forty-nine thousand, nine hundred thirty-six".