138787992 has 288 divisors, whose sum is σ = 478033920. Its totient is φ = 37558080.

The previous prime is 138787991. The next prime is 138788029. The reversal of 138787992 is 299787831.

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138787991) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2952913 + ... + 2952959.

It is an arithmetic number, because the mean of its divisors is an integer number (1659840).

Almost surely, 2^138787992 is an apocalyptic number.

138787992 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 138787992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (239016960).

138787992 is an abundant number, since it is smaller than the sum of its proper divisors (339245928).

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

138787992 is a wasteful number, since it uses less digits than its factorization.

138787992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 90 counting only the distinct ones).

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

The square root of 138787992 is about 11780.8315495978. The cubic root of 138787992 is about 517.7466499093.

The spelling of 138787992 in words is "one hundred thirty-eight million, seven hundred eighty-seven thousand, nine hundred ninety-two".