91155541 has 2 divisors, whose sum is σ = 91155542. Its totient is φ = 91155540.

The previous prime is 91155527. The next prime is 91155563. The reversal of 91155541 is 14555119.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78694641 + 12460900 = 8871^2 + 3530^2 .

It is a cyclic number.

It is not a de Polignac number, because 91155541 - 2¹¹ = 91153493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91155641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45577770 + 45577771.

It is an arithmetic number, because the mean of its divisors is an integer number (45577771).

Almost surely, 2^91155541 is an apocalyptic number.

It is an amenable number.

91155541 is a deficient number, since it is larger than the sum of its proper divisors (1).

91155541 is an equidigital number, since it uses as much as digits as its factorization.

91155541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4500, while the sum is 31.

The square root of 91155541 is about 9547.5410970574. The cubic root of 91155541 is about 450.0502676356.

The spelling of 91155541 in words is "ninety-one million, one hundred fifty-five thousand, five hundred forty-one".