81103700 has 18 divisors (see below), whose sum is σ = 175995246. Its totient is φ = 32441440.

The previous prime is 81103619. The next prime is 81103721. The reversal of 81103700 is 730118.

It can be written as a sum of positive squares in 3 ways, for example, as 31684 + 81072016 = 178^2 + 9004^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 405419 + ... + 405618.

Almost surely, 2^81103700 is an apocalyptic number.

It is an amenable number.

81103700 is an abundant number, since it is smaller than the sum of its proper divisors (94891546).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81103700 is a wasteful number, since it uses less digits than its factorization.

81103700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811051 (or 811044 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 81103700 is about 9005.7592683793. The cubic root of 81103700 is about 432.8594359079.

Adding to 81103700 its reverse (730118), we get a palindrome (81833818).

The spelling of 81103700 in words is "eighty-one million, one hundred three thousand, seven hundred".