138513720 has 64 divisors (see below), whose sum is σ = 420577920. Its totient is φ = 36489344.

The previous prime is 138513709. The next prime is 138513731. The reversal of 138513720 is 27315831.

It is an interprime number because it is at equal distance from previous prime (138513709) and next prime (138513731).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3007 + ... + 16913.

It is an arithmetic number, because the mean of its divisors is an integer number (6571530).

Almost surely, 2^138513720 is an apocalyptic number.

138513720 is a gapful number since it is divisible by the number (10) 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 138513720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210288960).

138513720 is an abundant number, since it is smaller than the sum of its proper divisors (282064200).

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

138513720 is a wasteful number, since it uses less digits than its factorization.

138513720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14004 (or 14000 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 138513720 is about 11769.1851884487. The cubic root of 138513720 is about 517.4053690534.

It can be divided in two parts, 13851 and 3720, that added together give a palindrome (17571).

The spelling of 138513720 in words is "one hundred thirty-eight million, five hundred thirteen thousand, seven hundred twenty".