138797550 has 120 divisors (see below), whose sum is σ = 395115336. Its totient is φ = 36106560.

The previous prime is 138797531. The next prime is 138797557. The reversal of 138797550 is 55797831.

138797550 is a `hidden beast` number, since 1 + 3 + 8 + 7 + 97 + 550 = 666.

138797550 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 138797496 and 138797505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138797557) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 173752 + ... + 174548.

Almost surely, 2^138797550 is an apocalyptic number.

138797550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 138797550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197557668).

138797550 is an abundant number, since it is smaller than the sum of its proper divisors (256317786).

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

138797550 is a wasteful number, since it uses less digits than its factorization.

138797550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864 (or 850 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 45.

The square root of 138797550 is about 11781.2372015846. The cubic root of 138797550 is about 517.7585349646.

The spelling of 138797550 in words is "one hundred thirty-eight million, seven hundred ninety-seven thousand, five hundred fifty".