643651146 has 12 divisors (see below), whose sum is σ = 1394577522. Its totient is φ = 214550376.

The previous prime is 643651121. The next prime is 643651181. The reversal of 643651146 is 641156346.

It is a happy number.

643651146 is a `hidden beast` number, since 643 + 6 + 5 + 1 + 1 + 4 + 6 = 666.

643651146 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 only one way, i.e., 623750625 + 19900521 = 24975^2 + 4461^2 .

It is a super-2 number, since 2×643651146² = 828573595494226632, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 643651146.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17879181 + ... + 17879216.

Almost surely, 2^643651146 is an apocalyptic number.

643651146 is an abundant number, since it is smaller than the sum of its proper divisors (750926376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643651146 is a wasteful number, since it uses less digits than its factorization.

643651146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35758405 (or 35758402 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 643651146 is about 25370.2807631291. The cubic root of 643651146 is about 863.4095518974.

The spelling of 643651146 in words is "six hundred forty-three million, six hundred fifty-one thousand, one hundred forty-six".