117829781 has 8 divisors (see below), whose sum is σ = 119158680. Its totient is φ = 116508672.

The previous prime is 117829757. The next prime is 117829861. The reversal of 117829781 is 187928711.

It can be written as a sum of positive squares in 4 ways, for example, as 7789681 + 110040100 = 2791^2 + 10490^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-117829781 is a prime.

It is a super-2 number, since 2×117829781² = 27767714581015922, 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 (117829721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31625 + ... + 35153.

It is an arithmetic number, because the mean of its divisors is an integer number (14894835).

Almost surely, 2^117829781 is an apocalyptic number.

It is an amenable number.

117829781 is a deficient number, since it is larger than the sum of its proper divisors (1328899).

117829781 is a wasteful number, since it uses less digits than its factorization.

117829781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3895.

The product of its digits is 56448, while the sum is 44.

The square root of 117829781 is about 10854.9426990657. The cubic root of 117829781 is about 490.2508517037.

The spelling of 117829781 in words is "one hundred seventeen million, eight hundred twenty-nine thousand, seven hundred eighty-one".