81950489694 has 32 divisors (see below), whose sum is σ = 183027360000. Its totient is φ = 27179555832.

The previous prime is 81950489681. The next prime is 81950489743. The reversal of 81950489694 is 49698405918.

81950489694 is a `hidden beast` number, since 8 + 1 + 95 + 0 + 489 + 69 + 4 = 666.

It is a super-2 number, since 2×81950489694² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3802324 + ... + 3823815.

It is an arithmetic number, because the mean of its divisors is an integer number (5719605000).

Almost surely, 2^81950489694 is an apocalyptic number.

81950489694 is an abundant number, since it is smaller than the sum of its proper divisors (101076870306).

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

81950489694 is a wasteful number, since it uses less digits than its factorization.

81950489694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7626349 (or 7626343 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 63.

The spelling of 81950489694 in words is "eighty-one billion, nine hundred fifty million, four hundred eighty-nine thousand, six hundred ninety-four".