138621791240 has 32 divisors (see below), whose sum is σ = 311910410880. Its totient is φ = 55446693312.

The previous prime is 138621791227. The next prime is 138621791249. The reversal of 138621791240 is 42197126831.

138621791240 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×138621791240² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138621791191 and 138621791200.

It is not an unprimeable number, because it can be changed into a prime (138621791249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1563377 + ... + 1649663.

It is an arithmetic number, because the mean of its divisors is an integer number (9747200340).

Almost surely, 2^138621791240 is an apocalyptic number.

138621791240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138621791240 is an abundant number, since it is smaller than the sum of its proper divisors (173288619640).

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

138621791240 is a wasteful number, since it uses less digits than its factorization.

138621791240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126461 (or 126457 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 44.

The spelling of 138621791240 in words is "one hundred thirty-eight billion, six hundred twenty-one million, seven hundred ninety-one thousand, two hundred forty".