117388821 has 16 divisors (see below), whose sum is σ = 179735040. Its totient is φ = 67399920.

The previous prime is 117388801. The next prime is 117388829. The reversal of 117388821 is 128883711.

It is not a de Polignac number, because 117388821 - 2¹⁵ = 117356053 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 117388821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (117388829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92985 + ... + 94238.

It is an arithmetic number, because the mean of its divisors is an integer number (11233440).

Almost surely, 2^117388821 is an apocalyptic number.

117388821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

117388821 is a deficient number, since it is larger than the sum of its proper divisors (62346219).

117388821 is a wasteful number, since it uses less digits than its factorization.

117388821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187256.

The product of its digits is 21504, while the sum is 39.

The square root of 117388821 is about 10834.6121758003. The cubic root of 117388821 is about 489.6385241844.

The spelling of 117388821 in words is "one hundred seventeen million, three hundred eighty-eight thousand, eight hundred twenty-one".