81085580051 has 8 divisors (see below), whose sum is σ = 98120365920. Its totient is φ = 65413577088.

The previous prime is 81085580047. The next prime is 81085580057. The reversal of 81085580051 is 15008558018.

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 81085580051 - 2² = 81085580047 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81085579990 and 81085580008.

It is not an unprimeable number, because it can be changed into a prime (81085580057) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 340695596 + ... + 340695833.

It is an arithmetic number, because the mean of its divisors is an integer number (12265045740).

Almost surely, 2^81085580051 is an apocalyptic number.

81085580051 is a deficient number, since it is larger than the sum of its proper divisors (17034785869).

81085580051 is a wasteful number, since it uses less digits than its factorization.

81085580051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681391453.

The product of its (nonzero) digits is 64000, while the sum is 41.

The spelling of 81085580051 in words is "eighty-one billion, eighty-five million, five hundred eighty thousand, fifty-one".