91550420201 has 2 divisors, whose sum is σ = 91550420202. Its totient is φ = 91550420200.

The previous prime is 91550420147. The next prime is 91550420233. The reversal of 91550420201 is 10202405519.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75679459801 + 15870960400 = 275099^2 + 125980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91550420201 is a prime.

It is not a weakly prime, because it can be changed into another prime (91550420281) 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 as a sum of consecutive naturals, namely, 45775210100 + 45775210101.

It is an arithmetic number, because the mean of its divisors is an integer number (45775210101).

Almost surely, 2^91550420201 is an apocalyptic number.

It is an amenable number.

91550420201 is a deficient number, since it is larger than the sum of its proper divisors (1).

91550420201 is an equidigital number, since it uses as much as digits as its factorization.

91550420201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 29.

The spelling of 91550420201 in words is "ninety-one billion, five hundred fifty million, four hundred twenty thousand, two hundred one".