91601391 has 8 divisors (see below), whose sum is σ = 139583104. Its totient is φ = 52343640.

The previous prime is 91601383. The next prime is 91601399. The reversal of 91601391 is 19310619.

It is an interprime number because it is at equal distance from previous prime (91601383) and next prime (91601399).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 91601391 - 2³ = 91601383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91601399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2180965 + ... + 2181006.

It is an arithmetic number, because the mean of its divisors is an integer number (17447888).

Almost surely, 2^91601391 is an apocalyptic number.

91601391 is a deficient number, since it is larger than the sum of its proper divisors (47981713).

91601391 is a wasteful number, since it uses less digits than its factorization.

91601391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4361981.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 91601391 is about 9570.8615599642. The cubic root of 91601391 is about 450.7828201323.

The spelling of 91601391 in words is "ninety-one million, six hundred one thousand, three hundred ninety-one".