81051155 has 8 divisors (see below), whose sum is σ = 102982752. Its totient is φ = 61026688.

The previous prime is 81051133. The next prime is 81051161. The reversal of 81051155 is 55115018.

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 81051155 - 2⁸ = 81050899 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 476687 + ... + 476856.

It is an arithmetic number, because the mean of its divisors is an integer number (12872844).

Almost surely, 2^81051155 is an apocalyptic number.

81051155 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

81051155 is a deficient number, since it is larger than the sum of its proper divisors (21931597).

81051155 is a wasteful number, since it uses less digits than its factorization.

81051155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 953565.

The product of its (nonzero) digits is 1000, while the sum is 26.

The square root of 81051155 is about 9002.8414958834. The cubic root of 81051155 is about 432.7659362167.

The spelling of 81051155 in words is "eighty-one million, fifty-one thousand, one hundred fifty-five".