91601259649 has 9 divisors (see below), whose sum is σ = 95764359873. Its totient is φ = 87611937732.

The previous prime is 91601259641. The next prime is 91601259653. The reversal of 91601259649 is 94695210619.

It is a happy number.

The square root of 91601259649 is 302657.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 91601259649 - 2³ = 91601259641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91601259596 and 91601259605.

It is not an unprimeable number, because it can be changed into a prime (91601259641) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 6954532 + ... + 6967690.

Almost surely, 2^91601259649 is an apocalyptic number.

91601259649 is the 302657-th square number.

91601259649 is the 151329-th centered octagonal number.

It is an amenable number.

91601259649 is a deficient number, since it is larger than the sum of its proper divisors (4163100224).

91601259649 is an frugal number, since it uses more digits than its factorization.

91601259649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26364 (or 13182 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 52.

The spelling of 91601259649 in words is "ninety-one billion, six hundred one million, two hundred fifty-nine thousand, six hundred forty-nine".