117891787 has 8 divisors (see below), whose sum is σ = 134428896. Its totient is φ = 102421632.

The previous prime is 117891749. The next prime is 117891797. The reversal of 117891787 is 787198711.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 117891787 - 2¹⁵ = 117859019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 117891787.

It is not an unprimeable number, because it can be changed into a prime (117891797) 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, 266503 + ... + 266944.

It is an arithmetic number, because the mean of its divisors is an integer number (16803612).

Almost surely, 2^117891787 is an apocalyptic number.

117891787 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

117891787 is a deficient number, since it is larger than the sum of its proper divisors (16537109).

117891787 is a wasteful number, since it uses less digits than its factorization.

117891787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533477.

The product of its digits is 197568, while the sum is 49.

The square root of 117891787 is about 10857.7984416732. The cubic root of 117891787 is about 490.3368321278.

The spelling of 117891787 in words is "one hundred seventeen million, eight hundred ninety-one thousand, seven hundred eighty-seven".