81956181295 has 16 divisors (see below), whose sum is σ = 99877142880. Its totient is φ = 64548417024.

The previous prime is 81956181257. The next prime is 81956181319. The reversal of 81956181295 is 59218165918.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81956181295 - 2⁹ = 81956180783 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5590 + ... + 404899.

It is an arithmetic number, because the mean of its divisors is an integer number (6242321430).

Almost surely, 2^81956181295 is an apocalyptic number.

81956181295 is a deficient number, since it is larger than the sum of its proper divisors (17920961585).

81956181295 is a wasteful number, since it uses less digits than its factorization.

81956181295 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411114.

The product of its digits is 1555200, while the sum is 55.

The spelling of 81956181295 in words is "eighty-one billion, nine hundred fifty-six million, one hundred eighty-one thousand, two hundred ninety-five".