138909399552 has 640 divisors, whose sum is σ = 526646292480. Its totient is φ = 35095265280.

The previous prime is 138909399547. The next prime is 138909399569. The reversal of 138909399552 is 255993909831.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a self number, because there is not a number n which added to its sum of digits gives 138909399552.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 39382813 + ... + 39386339.

It is an arithmetic number, because the mean of its divisors is an integer number (822884832).

Almost surely, 2^138909399552 is an apocalyptic number.

138909399552 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 138909399552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263323146240).

138909399552 is an abundant number, since it is smaller than the sum of its proper divisors (387736892928).

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

138909399552 is a wasteful number, since it uses less digits than its factorization.

138909399552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3609 (or 3587 counting only the distinct ones).

The product of its (nonzero) digits is 23619600, while the sum is 63.

The spelling of 138909399552 in words is "one hundred thirty-eight billion, nine hundred nine million, three hundred ninety-nine thousand, five hundred fifty-two".