113665121550 has 72 divisors (see below), whose sum is σ = 315910684440. Its totient is φ = 29265499200.

The previous prime is 113665121501. The next prime is 113665121551. The reversal of 113665121550 is 55121566311.

113665121550 is a `hidden beast` number, since 1 + 1 + 36 + 6 + 51 + 21 + 550 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (113665121551) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4341936 + ... + 4368035.

It is an arithmetic number, because the mean of its divisors is an integer number (4387648395).

Almost surely, 2^113665121550 is an apocalyptic number.

113665121550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

113665121550 is an abundant number, since it is smaller than the sum of its proper divisors (202245562890).

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

113665121550 is a wasteful number, since it uses less digits than its factorization.

113665121550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8710018 (or 8710010 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

Adding to 113665121550 its reverse (55121566311), we get a palindrome (168786687861).

The spelling of 113665121550 in words is "one hundred thirteen billion, six hundred sixty-five million, one hundred twenty-one thousand, five hundred fifty".