4520643991 has 2 divisors, whose sum is σ = 4520643992. Its totient is φ = 4520643990.

The previous prime is 4520643973. The next prime is 4520644003. The reversal of 4520643991 is 1993460254.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 4520643991 - 2⁷ = 4520643863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4520643931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2260321995 + 2260321996.

It is an arithmetic number, because the mean of its divisors is an integer number (2260321996).

Almost surely, 2^4520643991 is an apocalyptic number.

4520643991 is a deficient number, since it is larger than the sum of its proper divisors (1).

4520643991 is an equidigital number, since it uses as much as digits as its factorization.

4520643991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 4520643991 is about 67235.7344795162. The cubic root of 4520643991 is about 1653.4844016497.

The spelling of 4520643991 in words is "four billion, five hundred twenty million, six hundred forty-three thousand, nine hundred ninety-one".