1643920074 has 12 divisors (see below), whose sum is σ = 3561826866. Its totient is φ = 547973352.

The previous prime is 1643920039. The next prime is 1643920079. The reversal of 1643920074 is 4700293461.

1643920074 is a `hidden beast` number, since 1 + 643 + 9 + 2 + 0 + 0 + 7 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1335390849 + 308529225 = 36543^2 + 17565^2 .

It is not an unprimeable number, because it can be changed into a prime (1643920079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45664429 + ... + 45664464.

Almost surely, 2^1643920074 is an apocalyptic number.

1643920074 is an abundant number, since it is smaller than the sum of its proper divisors (1917906792).

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

1643920074 is a wasteful number, since it uses less digits than its factorization.

1643920074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91328901 (or 91328898 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 1643920074 is about 40545.2842387373. The cubic root of 1643920074 is about 1180.2125620138.

The spelling of 1643920074 in words is "one billion, six hundred forty-three million, nine hundred twenty thousand, seventy-four".