81697509467 has 16 divisors (see below), whose sum is σ = 103159153152. Its totient is φ = 63041700480.

The previous prime is 81697509449. The next prime is 81697509473. The reversal of 81697509467 is 76490579618.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81697509467 is a prime.

It is a super-2 number, since 2×81697509467² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81697509427) 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, 14921909 + ... + 14927382.

It is an arithmetic number, because the mean of its divisors is an integer number (6447447072).

Almost surely, 2^81697509467 is an apocalyptic number.

81697509467 is a deficient number, since it is larger than the sum of its proper divisors (21461643685).

81697509467 is a wasteful number, since it uses less digits than its factorization.

81697509467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29849338.

The product of its (nonzero) digits is 22861440, while the sum is 62.

The spelling of 81697509467 in words is "eighty-one billion, six hundred ninety-seven million, five hundred nine thousand, four hundred sixty-seven".