646877880 has 256 divisors, whose sum is σ = 2491430400. Its totient is φ = 147548160.

The previous prime is 646877827. The next prime is 646877927. The reversal of 646877880 is 88778646.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 200359 + ... + 203561.

It is an arithmetic number, because the mean of its divisors is an integer number (9732150).

Almost surely, 2^646877880 is an apocalyptic number.

646877880 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 646877880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1245715200).

646877880 is an abundant number, since it is smaller than the sum of its proper divisors (1844552520).

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

646877880 is a wasteful number, since it uses less digits than its factorization.

646877880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3251 (or 3241 counting only the distinct ones).

The product of its (nonzero) digits is 3612672, while the sum is 54.

The square root of 646877880 is about 25433.7940543679. The cubic root of 646877880 is about 864.8499544836.

It can be divided in two parts, 6468 and 77880, that added together give a palindrome (84348).

The spelling of 646877880 in words is "six hundred forty-six million, eight hundred seventy-seven thousand, eight hundred eighty".