91454688645421 has 2 divisors, whose sum is σ = 91454688645422. Its totient is φ = 91454688645420.

The previous prime is 91454688645407. The next prime is 91454688645451. The reversal of 91454688645421 is 12454688645419.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50089788927396 + 41364899718025 = 7077414^2 + 6431555^2 .

It is an emirp because it is prime and its reverse (12454688645419) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91454688645421 - 2⁵ = 91454688645389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91454688645451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45727344322710 + 45727344322711.

It is an arithmetic number, because the mean of its divisors is an integer number (45727344322711).

Almost surely, 2^{91454688645421} is an apocalyptic number.

It is an amenable number.

91454688645421 is a deficient number, since it is larger than the sum of its proper divisors (1).

91454688645421 is an equidigital number, since it uses as much as digits as its factorization.

91454688645421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 265420800, while the sum is 67.

The spelling of 91454688645421 in words is "ninety-one trillion, four hundred fifty-four billion, six hundred eighty-eight million, six hundred forty-five thousand, four hundred twenty-one".