646342164 has 72 divisors (see below), whose sum is σ = 1764846720. Its totient is φ = 198268992.

The previous prime is 646342141. The next prime is 646342187. The reversal of 646342164 is 461243646.

646342164 is a `hidden beast` number, since 6 + 4 + 634 + 2 + 16 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (646342141) and next prime (646342187).

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 166089 + ... + 169935.

It is an arithmetic number, because the mean of its divisors is an integer number (24511760).

Almost surely, 2^646342164 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 646342164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (882423360).

646342164 is an abundant number, since it is smaller than the sum of its proper divisors (1118504556).

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

646342164 is a wasteful number, since it uses less digits than its factorization.

646342164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4229 (or 4224 counting only the distinct ones).

The product of its digits is 82944, while the sum is 36.

The square root of 646342164 is about 25423.2602944626. The cubic root of 646342164 is about 864.6111448977.

The spelling of 646342164 in words is "six hundred forty-six million, three hundred forty-two thousand, one hundred sixty-four".