643066772 has 6 divisors (see below), whose sum is σ = 1125366858. Its totient is φ = 321533384.

The previous prime is 643066757. The next prime is 643066813. The reversal of 643066772 is 277660346.

It can be written as a sum of positive squares in only one way, i.e., 542144656 + 100922116 = 23284^2 + 10046^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80383343 + ... + 80383350.

It is an arithmetic number, because the mean of its divisors is an integer number (187561143).

Almost surely, 2^643066772 is an apocalyptic number.

It is an amenable number.

643066772 is a deficient number, since it is larger than the sum of its proper divisors (482300086).

643066772 is a wasteful number, since it uses less digits than its factorization.

643066772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160766697 (or 160766695 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 41.

The square root of 643066772 is about 25358.7612473480. The cubic root of 643066772 is about 863.1481748718.

The spelling of 643066772 in words is "six hundred forty-three million, sixty-six thousand, seven hundred seventy-two".