91004032061 has 4 divisors (see below), whose sum is σ = 91161751932. Its totient is φ = 90846312192.

The previous prime is 91004032051. The next prime is 91004032079. The reversal of 91004032061 is 16023040019.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 89994000100 + 1010031961 = 299990^2 + 31781^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91004032061 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91004032061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91004032051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78859070 + ... + 78860223.

It is an arithmetic number, because the mean of its divisors is an integer number (22790437983).

Almost surely, 2^91004032061 is an apocalyptic number.

It is an amenable number.

91004032061 is a deficient number, since it is larger than the sum of its proper divisors (157719871).

91004032061 is a wasteful number, since it uses less digits than its factorization.

91004032061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157719870.

The product of its (nonzero) digits is 1296, while the sum is 26.

The spelling of 91004032061 in words is "ninety-one billion, four million, thirty-two thousand, sixty-one".