81694005 has 16 divisors (see below), whose sum is σ = 131392320. Its totient is φ = 43342848.

The previous prime is 81694003. The next prime is 81694013. The reversal of 81694005 is 50049618.

It is not a de Polignac number, because 81694005 - 2¹ = 81694003 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81694003) 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, 11215 + ... + 17004.

It is an arithmetic number, because the mean of its divisors is an integer number (8212020).

Almost surely, 2^81694005 is an apocalyptic number.

It is an amenable number.

81694005 is a deficient number, since it is larger than the sum of its proper divisors (49698315).

81694005 is a wasteful number, since it uses less digits than its factorization.

81694005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28420.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 81694005 is about 9038.4735990100. The cubic root of 81694005 is about 433.9070727017.

The spelling of 81694005 in words is "eighty-one million, six hundred ninety-four thousand, five".