643100477 has 2 divisors, whose sum is σ = 643100478. Its totient is φ = 643100476.

The previous prime is 643100473. The next prime is 643100519. The reversal of 643100477 is 774001346.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 523219876 + 119880601 = 22874^2 + 10949^2 .

It is a cyclic number.

It is not a de Polignac number, because 643100477 - 2² = 643100473 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643100473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321550238 + 321550239.

It is an arithmetic number, because the mean of its divisors is an integer number (321550239).

Almost surely, 2^643100477 is an apocalyptic number.

It is an amenable number.

643100477 is a deficient number, since it is larger than the sum of its proper divisors (1).

643100477 is an equidigital number, since it uses as much as digits as its factorization.

643100477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 643100477 is about 25359.4258018592. The cubic root of 643100477 is about 863.1632546438.

The spelling of 643100477 in words is "six hundred forty-three million, one hundred thousand, four hundred seventy-seven".