117151781 has 4 divisors (see below), whose sum is σ = 119072364. Its totient is φ = 115231200.

The previous prime is 117151747. The next prime is 117151789. The reversal of 117151781 is 187151711.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 48427681 + 68724100 = 6959^2 + 8290^2 .

It is a cyclic number.

It is not a de Polignac number, because 117151781 - 2⁶ = 117151717 is a prime.

It is a super-2 number, since 2×117151781² = 27449079582943922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (117151789) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 960200 + ... + 960321.

It is an arithmetic number, because the mean of its divisors is an integer number (29768091).

Almost surely, 2^117151781 is an apocalyptic number.

It is an amenable number.

117151781 is a deficient number, since it is larger than the sum of its proper divisors (1920583).

117151781 is an equidigital number, since it uses as much as digits as its factorization.

117151781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1920582.

The product of its digits is 1960, while the sum is 32.

The square root of 117151781 is about 10823.6676316302. The cubic root of 117151781 is about 489.3087309267.

The spelling of 117151781 in words is "one hundred seventeen million, one hundred fifty-one thousand, seven hundred eighty-one".