643465127 has 2 divisors, whose sum is σ = 643465128. Its totient is φ = 643465126.

The previous prime is 643465093. The next prime is 643465139. The reversal of 643465127 is 721564346.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643465127 - 2¹⁰ = 643464103 is a prime.

It is a super-2 number, since 2×643465127² = 828094739330252258, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643468127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321732563 + 321732564.

It is an arithmetic number, because the mean of its divisors is an integer number (321732564).

Almost surely, 2^643465127 is an apocalyptic number.

643465127 is a deficient number, since it is larger than the sum of its proper divisors (1).

643465127 is an equidigital number, since it uses as much as digits as its factorization.

643465127 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 38.

The square root of 643465127 is about 25366.6144173794. The cubic root of 643465127 is about 863.3263670555.

The spelling of 643465127 in words is "six hundred forty-three million, four hundred sixty-five thousand, one hundred twenty-seven".