81511103 has 8 divisors (see below), whose sum is σ = 85600608. Its totient is φ = 77467104.

The previous prime is 81511097. The next prime is 81511117. The reversal of 81511103 is 30111518.

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 81511103 - 2¹² = 81507007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81511153) 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, 7676 + ... + 14897.

It is an arithmetic number, because the mean of its divisors is an integer number (10700076).

Almost surely, 2^81511103 is an apocalyptic number.

81511103 is a deficient number, since it is larger than the sum of its proper divisors (4089505).

81511103 is a wasteful number, since it uses less digits than its factorization.

81511103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22753.

The product of its (nonzero) digits is 120, while the sum is 20.

The square root of 81511103 is about 9028.3499599872. The cubic root of 81511103 is about 433.5830106830.

The spelling of 81511103 in words is "eighty-one million, five hundred eleven thousand, one hundred three".