643798074 has 8 divisors (see below), whose sum is σ = 1287596160. Its totient is φ = 214599356.

The previous prime is 643798073. The next prime is 643798081. The reversal of 643798074 is 470897346.

It is a happy number.

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

643798074 is an admirable number.

It is a super-2 number, since 2×643798074² = 828951920172218952, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (643798073) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53649834 + ... + 53649845.

It is an arithmetic number, because the mean of its divisors is an integer number (160949520).

Almost surely, 2^643798074 is an apocalyptic number.

643798074 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

643798074 is a wasteful number, since it uses less digits than its factorization.

643798074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107299684.

The product of its (nonzero) digits is 1016064, while the sum is 48.

The square root of 643798074 is about 25373.1762694386. The cubic root of 643798074 is about 863.4752445156.

The spelling of 643798074 in words is "six hundred forty-three million, seven hundred ninety-eight thousand, seventy-four".