1646407680 has 208 divisors, whose sum is σ = 5334503424. Its totient is φ = 433520640.

The previous prime is 1646407673. The next prime is 1646407681. The reversal of 1646407680 is 867046461.

It is not an unprimeable number, because it can be changed into a prime (1646407681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7802775 + ... + 7802985.

Almost surely, 2^1646407680 is an apocalyptic number.

1646407680 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 1646407680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2667251712).

1646407680 is an abundant number, since it is smaller than the sum of its proper divisors (3688095744).

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

1646407680 is a wasteful number, since it uses less digits than its factorization.

1646407680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 42.

The square root of 1646407680 is about 40575.9495267825. The cubic root of 1646407680 is about 1180.8075674635.

The spelling of 1646407680 in words is "one billion, six hundred forty-six million, four hundred seven thousand, six hundred eighty".