643277401 has 8 divisors (see below), whose sum is σ = 692987400. Its totient is φ = 593599872.

The previous prime is 643277389. The next prime is 643277407. The reversal of 643277401 is 104772346.

643277401 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 56475225 + 586802176 = 7515^2 + 24224^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643277401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643277407) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46875 + ... + 59023.

It is an arithmetic number, because the mean of its divisors is an integer number (86623425).

Almost surely, 2^643277401 is an apocalyptic number.

It is an amenable number.

643277401 is a deficient number, since it is larger than the sum of its proper divisors (49709999).

643277401 is a wasteful number, since it uses less digits than its factorization.

643277401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16235.

The product of its (nonzero) digits is 28224, while the sum is 34.

The square root of 643277401 is about 25362.9138901665. The cubic root of 643277401 is about 863.2424026146.

The spelling of 643277401 in words is "six hundred forty-three million, two hundred seventy-seven thousand, four hundred one".