646394364 has 192 divisors, whose sum is σ = 2199859200. Its totient is φ = 159019200.

The previous prime is 646394363. The next prime is 646394389. The reversal of 646394364 is 463493646.

646394364 is a `hidden beast` number, since 6 + 4 + 639 + 4 + 3 + 6 + 4 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646394363) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 155959 + ... + 160049.

It is an arithmetic number, because the mean of its divisors is an integer number (11457600).

Almost surely, 2^646394364 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646394364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1099929600).

646394364 is an abundant number, since it is smaller than the sum of its proper divisors (1553464836).

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

646394364 is a wasteful number, since it uses less digits than its factorization.

646394364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4141 (or 4133 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 45.

The square root of 646394364 is about 25424.2868926544. The cubic root of 646394364 is about 864.6344202305.

The spelling of 646394364 in words is "six hundred forty-six million, three hundred ninety-four thousand, three hundred sixty-four".