81103508 has 6 divisors (see below), whose sum is σ = 141931146. Its totient is φ = 40551752.

The previous prime is 81103507. The next prime is 81103523. The reversal of 81103508 is 80530118.

It can be written as a sum of positive squares in only one way, i.e., 77651344 + 3452164 = 8812^2 + 1858^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81103507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10137935 + ... + 10137942.

It is an arithmetic number, because the mean of its divisors is an integer number (23655191).

Almost surely, 2^81103508 is an apocalyptic number.

It is an amenable number.

81103508 is a deficient number, since it is larger than the sum of its proper divisors (60827638).

81103508 is a wasteful number, since it uses less digits than its factorization.

81103508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20275881 (or 20275879 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 81103508 is about 9005.7486085278. The cubic root of 81103508 is about 432.8590943325.

The spelling of 81103508 in words is "eighty-one million, one hundred three thousand, five hundred eight".