91316321506 has 4 divisors (see below), whose sum is σ = 136974482262. Its totient is φ = 45658160752.

The previous prime is 91316321471. The next prime is 91316321531. The reversal of 91316321506 is 60512361319.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60512361319 = 29573 ⋅2046203.

It can be written as a sum of positive squares in only one way, i.e., 89841070225 + 1475251281 = 299735^2 + 38409^2 .

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 as a sum of consecutive naturals, namely, 22829080375 + ... + 22829080378.

Almost surely, 2^91316321506 is an apocalyptic number.

91316321506 is a deficient number, since it is larger than the sum of its proper divisors (45658160756).

91316321506 is a wasteful number, since it uses less digits than its factorization.

91316321506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45658160755.

The product of its (nonzero) digits is 29160, while the sum is 37.

The spelling of 91316321506 in words is "ninety-one billion, three hundred sixteen million, three hundred twenty-one thousand, five hundred six".