81780113 has 8 divisors (see below), whose sum is σ = 83654208. Its totient is φ = 79918384.

The previous prime is 81780107. The next prime is 81780119. The reversal of 81780113 is 31108718.

It is an interprime number because it is at equal distance from previous prime (81780107) and next prime (81780119).

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 81780113 - 2²⁰ = 80731537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81780119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11006 + ... + 16872.

It is an arithmetic number, because the mean of its divisors is an integer number (10456776).

Almost surely, 2^81780113 is an apocalyptic number.

It is an amenable number.

81780113 is a deficient number, since it is larger than the sum of its proper divisors (1874095).

81780113 is a wasteful number, since it uses less digits than its factorization.

81780113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6183.

The product of its (nonzero) digits is 1344, while the sum is 29.

The square root of 81780113 is about 9043.2357593950. The cubic root of 81780113 is about 434.0594696481.

The spelling of 81780113 in words is "eighty-one million, seven hundred eighty thousand, one hundred thirteen".