81907195547 has 8 divisors (see below), whose sum is σ = 82319660640. Its totient is φ = 81495207360.

The previous prime is 81907195529. The next prime is 81907195561. The reversal of 81907195547 is 74559170918.

It is a happy number.

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 81907195547 - 2³⁶ = 13187718811 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81907195492 and 81907195501.

It is not an unprimeable number, because it can be changed into a prime (81907195567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 227663 + ... + 464375.

It is an arithmetic number, because the mean of its divisors is an integer number (10289957580).

Almost surely, 2^81907195547 is an apocalyptic number.

81907195547 is a deficient number, since it is larger than the sum of its proper divisors (412465093).

81907195547 is a wasteful number, since it uses less digits than its factorization.

81907195547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238453.

The product of its (nonzero) digits is 3175200, while the sum is 56.

The spelling of 81907195547 in words is "eighty-one billion, nine hundred seven million, one hundred ninety-five thousand, five hundred forty-seven".