81694995 has 16 divisors (see below), whose sum is σ = 133179552. Its totient is φ = 42748160.

The previous prime is 81694993. The next prime is 81695023. The reversal of 81694995 is 59949618.

It is not a de Polignac number, because 81694995 - 2¹ = 81694993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81694993) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 50586 + ... + 52175.

It is an arithmetic number, because the mean of its divisors is an integer number (8323722).

Almost surely, 2^81694995 is an apocalyptic number.

81694995 is a deficient number, since it is larger than the sum of its proper divisors (51484557).

81694995 is a wasteful number, since it uses less digits than its factorization.

81694995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102822.

The product of its digits is 699840, while the sum is 51.

The square root of 81694995 is about 9038.5283647284. The cubic root of 81694995 is about 433.9088254467.

The spelling of 81694995 in words is "eighty-one million, six hundred ninety-four thousand, nine hundred ninety-five".