138515520 has 224 divisors, whose sum is σ = 517184640. Its totient is φ = 30965760.

The previous prime is 138515501. The next prime is 138515527. The reversal of 138515520 is 25515831.

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

It is not an unprimeable number, because it can be changed into a prime (138515527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 136776 + ... + 137784.

It is an arithmetic number, because the mean of its divisors is an integer number (2308860).

Almost surely, 2^138515520 is an apocalyptic number.

138515520 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 138515520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258592320).

138515520 is an abundant number, since it is smaller than the sum of its proper divisors (378669120).

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

138515520 is a wasteful number, since it uses less digits than its factorization.

138515520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1053 (or 1043 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 30.

The square root of 138515520 is about 11769.2616590847. The cubic root of 138515520 is about 517.4076102890.

The spelling of 138515520 in words is "one hundred thirty-eight million, five hundred fifteen thousand, five hundred twenty".