81099056477 has 8 divisors (see below), whose sum is σ = 82084611840. Its totient is φ = 80119054080.

The previous prime is 81099056443. The next prime is 81099056491. The reversal of 81099056477 is 77465099018.

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 81099056477 - 2¹⁸ = 81098794333 is a prime.

It is a super-2 number, since 2×81099056477² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81099056407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1358852 + ... + 1417277.

It is an arithmetic number, because the mean of its divisors is an integer number (10260576480).

Almost surely, 2^81099056477 is an apocalyptic number.

It is an amenable number.

81099056477 is a deficient number, since it is larger than the sum of its proper divisors (985555363).

81099056477 is a wasteful number, since it uses less digits than its factorization.

81099056477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2776483.

The product of its (nonzero) digits is 3810240, while the sum is 56.

The spelling of 81099056477 in words is "eighty-one billion, ninety-nine million, fifty-six thousand, four hundred seventy-seven".