81249795 has 96 divisors (see below), whose sum is σ = 165784320. Its totient is φ = 36391680.

The previous prime is 81249787. The next prime is 81249811. The reversal of 81249795 is 59794218.

It is not a de Polignac number, because 81249795 - 2³ = 81249787 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 81249795.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 498384 + ... + 498546.

It is an arithmetic number, because the mean of its divisors is an integer number (1726920).

It is a vampire number, since it can be written as 8745 ⋅ 9291 (with its own digits).

Almost surely, 2^81249795 is an apocalyptic number.

81249795 is an abundant number, since it is smaller than the sum of its proper divisors (84534525).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81249795 is a wasteful number, since it uses less digits than its factorization.

81249795 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 254 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 81249795 is about 9013.8668172988. The cubic root of 81249795 is about 433.1191884055.

The spelling of 81249795 in words is "eighty-one million, two hundred forty-nine thousand, seven hundred ninety-five".