643461501 has 16 divisors (see below), whose sum is σ = 908619264. Its totient is φ = 404196144.

The previous prime is 643461491. The next prime is 643461523. The reversal of 643461501 is 105164346.

It is not a de Polignac number, because 643461501 - 2²⁵ = 609907069 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643461551) 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 in 15 ways as a sum of consecutive naturals, for example, 64971 + ... + 74216.

It is an arithmetic number, because the mean of its divisors is an integer number (56788704).

Almost surely, 2^643461501 is an apocalyptic number.

It is an amenable number.

643461501 is a deficient number, since it is larger than the sum of its proper divisors (265157763).

643461501 is a wasteful number, since it uses less digits than its factorization.

643461501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139280.

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 643461501 is about 25366.5429453838. The cubic root of 643461501 is about 863.3247454047.

The spelling of 643461501 in words is "six hundred forty-three million, four hundred sixty-one thousand, five hundred one".