1646143680 has 112 divisors (see below), whose sum is σ = 5240206944. Its totient is φ = 437821440.

The previous prime is 1646143669. The next prime is 1646143693. The reversal of 1646143680 is 863416461.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 402124 + ... + 406196.

It is an arithmetic number, because the mean of its divisors is an integer number (46787562).

Almost surely, 2^1646143680 is an apocalyptic number.

1646143680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1646143680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2620103472).

1646143680 is an abundant number, since it is smaller than the sum of its proper divisors (3594063264).

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

1646143680 is a wasteful number, since it uses less digits than its factorization.

1646143680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4514 (or 4504 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 39.

The square root of 1646143680 is about 40572.6962377410. The cubic root of 1646143680 is about 1180.7444502771.

The spelling of 1646143680 in words is "one billion, six hundred forty-six million, one hundred forty-three thousand, six hundred eighty".