138858240 has 72 divisors (see below), whose sum is σ = 443490768. Its totient is φ = 37027840.

The previous prime is 138858229. The next prime is 138858259. The reversal of 138858240 is 42858831.

It is a super-2 number, since 2×138858240² = 38563221631795200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14241 + ... + 21920.

It is an arithmetic number, because the mean of its divisors is an integer number (6159594).

Almost surely, 2^138858240 is an apocalyptic number.

138858240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138858240 is an abundant number, since it is smaller than the sum of its proper divisors (304632528).

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

138858240 is an equidigital number, since it uses as much as digits as its factorization.

138858240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36185 (or 36171 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 39.

The square root of 138858240 is about 11783.8126258015. The cubic root of 138858240 is about 517.8339882337.

The spelling of 138858240 in words is "one hundred thirty-eight million, eight hundred fifty-eight thousand, two hundred forty".