81047811377 has 16 divisors (see below), whose sum is σ = 93039072000. Its totient is φ = 69978639744.

The previous prime is 81047811307. The next prime is 81047811391. The reversal of 81047811377 is 77311874018.

It is not a de Polignac number, because 81047811377 - 2²⁰ = 81046762801 is a prime.

It is a super-2 number, since 2×81047811377² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81047811307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2057252 + ... + 2096277.

It is an arithmetic number, because the mean of its divisors is an integer number (5814942000).

Almost surely, 2^81047811377 is an apocalyptic number.

It is an amenable number.

81047811377 is a deficient number, since it is larger than the sum of its proper divisors (11991260623).

81047811377 is a wasteful number, since it uses less digits than its factorization.

81047811377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4153640.

The product of its (nonzero) digits is 263424, while the sum is 47.

The spelling of 81047811377 in words is "eighty-one billion, forty-seven million, eight hundred eleven thousand, three hundred seventy-seven".