4491508785121 has 2 divisors, whose sum is σ = 4491508785122. Its totient is φ = 4491508785120.

The previous prime is 4491508785103. The next prime is 4491508785151. The reversal of 4491508785121 is 1215878051944.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3565718432721 + 925790352400 = 1888311^2 + 962180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4491508785121 is a prime.

It is not a weakly prime, because it can be changed into another prime (4491508785151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2245754392560 + 2245754392561.

It is an arithmetic number, because the mean of its divisors is an integer number (2245754392561).

Almost surely, 2^{4491508785121} is an apocalyptic number.

It is an amenable number.

4491508785121 is a deficient number, since it is larger than the sum of its proper divisors (1).

4491508785121 is an equidigital number, since it uses as much as digits as its factorization.

4491508785121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3225600, while the sum is 55.

The spelling of 4491508785121 in words is "four trillion, four hundred ninety-one billion, five hundred eight million, seven hundred eighty-five thousand, one hundred twenty-one".