138799872 has 144 divisors (see below), whose sum is σ = 420900480. Its totient is φ = 45093888.

The previous prime is 138799847. The next prime is 138799873. The reversal of 138799872 is 278997831.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (138799873) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 296983 + ... + 297449.

It is an arithmetic number, because the mean of its divisors is an integer number (2922920).

Almost surely, 2^138799872 is an apocalyptic number.

138799872 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 138799872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210450240).

138799872 is an abundant number, since it is smaller than the sum of its proper divisors (282100608).

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

138799872 is an equidigital number, since it uses as much as digits as its factorization.

138799872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535 (or 515 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 54.

The square root of 138799872 is about 11781.3357476986. The cubic root of 138799872 is about 517.7614222121.

The spelling of 138799872 in words is "one hundred thirty-eight million, seven hundred ninety-nine thousand, eight hundred seventy-two".