1628779680 has 432 divisors, whose sum is σ = 6323964192. Its totient is φ = 378547200.

The previous prime is 1628779679. The next prime is 1628779687. The reversal of 1628779680 is 869778261.

1628779680 is a `hidden beast` number, since 1 + 628 + 7 + 7 + 9 + 6 + 8 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (1628779687) by changing a digit.

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 71 ways as a sum of consecutive naturals, for example, 15222187 + ... + 15222293.

It is an arithmetic number, because the mean of its divisors is an integer number (14638806).

Almost surely, 2^1628779680 is an apocalyptic number.

1628779680 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 1628779680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3161982096).

1628779680 is an abundant number, since it is smaller than the sum of its proper divisors (4695184512).

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

1628779680 is a wasteful number, since it uses less digits than its factorization.

1628779680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The square root of 1628779680 is about 40358.1426728238. The cubic root of 1628779680 is about 1176.5781552548.

The spelling of 1628779680 in words is "one billion, six hundred twenty-eight million, seven hundred seventy-nine thousand, six hundred eighty".