138487968 has 180 divisors, whose sum is σ = 429982938. Its totient is φ = 43718400.

The previous prime is 138487961. The next prime is 138487997. The reversal of 138487968 is 869784831.

It can be written as a sum of positive squares in only one way, i.e., 82955664 + 55532304 = 9108^2 + 7452^2 .

It is a super-3 number, since 3×138487968³ (a number of 25 digits) contains 333 as substring.

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 (138487961) 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 29 ways as a sum of consecutive naturals, for example, 1371118 + ... + 1371218.

Almost surely, 2^138487968 is an apocalyptic number.

138487968 is a gapful number since it is divisible by the number (18) 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 138487968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214991469).

138487968 is an abundant number, since it is smaller than the sum of its proper divisors (291494970).

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

138487968 is a wasteful number, since it uses less digits than its factorization.

138487968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169 (or 129 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The square root of 138487968 is about 11768.0910941410. The cubic root of 138487968 is about 517.3733023169.

The spelling of 138487968 in words is "one hundred thirty-eight million, four hundred eighty-seven thousand, nine hundred sixty-eight".