646188480 has 504 divisors, whose sum is σ = 2732867280. Its totient is φ = 139345920.

The previous prime is 646188457. The next prime is 646188493. The reversal of 646188480 is 84881646.

It is a tau number, because it is divible by the number of its divisors (504).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2681160 + ... + 2681400.

Almost surely, 2^646188480 is an apocalyptic number.

646188480 is a gapful number since it is divisible by the number (60) 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 646188480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1366433640).

646188480 is an abundant number, since it is smaller than the sum of its proper divisors (2086678800).

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

646188480 is a wasteful number, since it uses less digits than its factorization.

646188480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 45.

The square root of 646188480 is about 25420.2376070720. The cubic root of 646188480 is about 864.5426118309.

The spelling of 646188480 in words is "six hundred forty-six million, one hundred eighty-eight thousand, four hundred eighty".