81692089208 has 32 divisors (see below), whose sum is σ = 154771344000. Its totient is φ = 40421624160.

The previous prime is 81692089207. The next prime is 81692089231. The reversal of 81692089208 is 80298029618.

It is a self number, because there is not a number n which added to its sum of digits gives 81692089208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81692089207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 227723 + ... + 463941.

It is an arithmetic number, because the mean of its divisors is an integer number (4836604500).

Almost surely, 2^81692089208 is an apocalyptic number.

It is an amenable number.

81692089208 is a deficient number, since it is larger than the sum of its proper divisors (73079254792).

81692089208 is a wasteful number, since it uses less digits than its factorization.

81692089208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236675 (or 236671 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 53.

The spelling of 81692089208 in words is "eighty-one billion, six hundred ninety-two million, eighty-nine thousand, two hundred eight".