91000000016 has 10 divisors (see below), whose sum is σ = 176312500062. Its totient is φ = 45500000000.

The previous prime is 90999999973. The next prime is 91000000037. The reversal of 91000000016 is 61000000019.

It can be written as a sum of positive squares in only one way, i.e., 79975840000 + 11024160016 = 282800^2 + 104996^2 .

91000000016 is a strobogrammatic number because it is the same when read upside-down.

It is a junction number, because it is equal to n+sod(n) for n = 90999999940 and 91000000003.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2843749985 + ... + 2843750016.

Almost surely, 2^91000000016 is an apocalyptic number.

It is an amenable number.

91000000016 is a deficient number, since it is larger than the sum of its proper divisors (85312500046).

91000000016 is a wasteful number, since it uses less digits than its factorization.

91000000016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5687500009 (or 5687500003 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 17.

The spelling of 91000000016 in words is "ninety-one billion, sixteen", and thus it is an aban number and an uban number.