117578861 has 2 divisors, whose sum is σ = 117578862. Its totient is φ = 117578860.

The previous prime is 117578831. The next prime is 117578863. The reversal of 117578861 is 168875711.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88472836 + 29106025 = 9406^2 + 5395^2 .

It is a cyclic number.

It is not a de Polignac number, because 117578861 - 2¹⁴ = 117562477 is a prime.

Together with 117578863, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (117578863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 58789430 + 58789431.

It is an arithmetic number, because the mean of its divisors is an integer number (58789431).

Almost surely, 2^117578861 is an apocalyptic number.

It is an amenable number.

117578861 is a deficient number, since it is larger than the sum of its proper divisors (1).

117578861 is an equidigital number, since it uses as much as digits as its factorization.

117578861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94080, while the sum is 44.

The square root of 117578861 is about 10843.3786708756. The cubic root of 117578861 is about 489.9026059379.

The spelling of 117578861 in words is "one hundred seventeen million, five hundred seventy-eight thousand, eight hundred sixty-one".