81465225547 has 16 divisors (see below), whose sum is σ = 88648892640. Its totient is φ = 74562872832.

The previous prime is 81465225533. The next prime is 81465225617. The reversal of 81465225547 is 74552256418.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81465225547 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81465225547.

It is not an unprimeable number, because it can be changed into a prime (81465220547) 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, 75928 + ... + 410725.

It is an arithmetic number, because the mean of its divisors is an integer number (5540555790).

Almost surely, 2^81465225547 is an apocalyptic number.

81465225547 is a deficient number, since it is larger than the sum of its proper divisors (7183667093).

81465225547 is a wasteful number, since it uses less digits than its factorization.

81465225547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 486942.

The product of its digits is 2688000, while the sum is 49.

The spelling of 81465225547 in words is "eighty-one billion, four hundred sixty-five million, two hundred twenty-five thousand, five hundred forty-seven".