138791340 has 96 divisors (see below), whose sum is σ = 445777920. Its totient is φ = 35812800.

The previous prime is 138791339. The next prime is 138791347. The reversal of 138791340 is 43197831.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 138791295 and 138791304.

It is not an unprimeable number, because it can be changed into a prime (138791347) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12595 + ... + 20885.

It is an arithmetic number, because the mean of its divisors is an integer number (4643520).

Almost surely, 2^138791340 is an apocalyptic number.

138791340 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 138791340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222888960).

138791340 is an abundant number, since it is smaller than the sum of its proper divisors (306986580).

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

138791340 is a wasteful number, since it uses less digits than its factorization.

138791340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8340 (or 8332 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 138791340 is about 11780.9736439736. The cubic root of 138791340 is about 517.7508130981.

The spelling of 138791340 in words is "one hundred thirty-eight million, seven hundred ninety-one thousand, three hundred forty".