643575487 has 2 divisors, whose sum is σ = 643575488. Its totient is φ = 643575486.

The previous prime is 643575479. The next prime is 643575523. The reversal of 643575487 is 784575346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643575487 - 2³ = 643575479 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643575487.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643573487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321787743 + 321787744.

It is an arithmetic number, because the mean of its divisors is an integer number (321787744).

Almost surely, 2^643575487 is an apocalyptic number.

643575487 is a deficient number, since it is larger than the sum of its proper divisors (1).

643575487 is an equidigital number, since it uses as much as digits as its factorization.

643575487 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2822400, while the sum is 49.

The square root of 643575487 is about 25368.7896242608. The cubic root of 643575487 is about 863.3757202877.

The spelling of 643575487 in words is "six hundred forty-three million, five hundred seventy-five thousand, four hundred eighty-seven".