646143819 has 8 divisors (see below), whose sum is σ = 889316352. Its totient is φ = 416866920.

The previous prime is 646143793. The next prime is 646143859. The reversal of 646143819 is 918341646.

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

It is not a de Polignac number, because 646143819 - 2¹⁵ = 646111051 is a prime.

It is a super-2 number, since 2×646143819² = 835003669663809522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (646143859) 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, 3473799 + ... + 3473984.

It is an arithmetic number, because the mean of its divisors is an integer number (111164544).

Almost surely, 2^646143819 is an apocalyptic number.

646143819 is a deficient number, since it is larger than the sum of its proper divisors (243172533).

646143819 is a wasteful number, since it uses less digits than its factorization.

646143819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6947817.

The product of its digits is 124416, while the sum is 42.

The square root of 646143819 is about 25419.3591382631. The cubic root of 646143819 is about 864.5226938924.

The spelling of 646143819 in words is "six hundred forty-six million, one hundred forty-three thousand, eight hundred nineteen".