646354044 has 72 divisors (see below), whose sum is σ = 1884774528. Its totient is φ = 182939040.

The previous prime is 646354043. The next prime is 646354057. The reversal of 646354044 is 440453646.

646354044 is a `hidden beast` number, since 646 + 3 + 5 + 4 + 0 + 4 + 4 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646354043) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14979 + ... + 38949.

It is an arithmetic number, because the mean of its divisors is an integer number (26177424).

Almost surely, 2^646354044 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 646354044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (942387264).

646354044 is an abundant number, since it is smaller than the sum of its proper divisors (1238420484).

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

646354044 is a wasteful number, since it uses less digits than its factorization.

646354044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24095 (or 24090 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 36.

The square root of 646354044 is about 25423.4939376947. The cubic root of 646354044 is about 864.6164421526.

The spelling of 646354044 in words is "six hundred forty-six million, three hundred fifty-four thousand, forty-four".