113861781 has 32 divisors (see below), whose sum is σ = 186330240. Its totient is φ = 68992560.

The previous prime is 113861779. The next prime is 113861789. The reversal of 113861781 is 187168311.

It is a happy number.

113861781 is a `hidden beast` number, since 1 + 1 + 38 + 617 + 8 + 1 = 666.

It is not a de Polignac number, because 113861781 - 2¹ = 113861779 is a prime.

It is a super-2 number, since 2×113861781² = 25929010344983922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (113861789) 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 31 ways as a sum of consecutive naturals, for example, 21691 + ... + 26423.

It is an arithmetic number, because the mean of its divisors is an integer number (5822820).

Almost surely, 2^113861781 is an apocalyptic number.

113861781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

113861781 is a deficient number, since it is larger than the sum of its proper divisors (72468459).

113861781 is an frugal number, since it uses more digits than its factorization.

113861781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4765 (or 4747 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 113861781 is about 10670.6035911751. The cubic root of 113861781 is about 484.6847151986.

The spelling of 113861781 in words is "one hundred thirteen million, eight hundred sixty-one thousand, seven hundred eighty-one".