1028081664 has 216 divisors, whose sum is σ = 3170570130. Its totient is φ = 320864256.

The previous prime is 1028081641. The next prime is 1028081671. The reversal of 1028081664 is 4661808201.

It can be written as a sum of positive squares in 3 ways, for example, as 973440000 + 54641664 = 31200^2 + 7392^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 17 ways as a sum of consecutive naturals, for example, 5326752 + ... + 5326944.

Almost surely, 2^1028081664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1028081664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1585285065).

1028081664 is an abundant number, since it is smaller than the sum of its proper divisors (2142488466).

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

1028081664 is a wasteful number, since it uses less digits than its factorization.

1028081664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 1028081664 is about 32063.7125735620. The cubic root of 1028081664 is about 1009.2742765606.

Adding to 1028081664 its product of nonzero digits (18432), we get a square (1028100096 = 32064²).

Adding to 1028081664 its reverse (4661808201), we get a palindrome (5689889865).

The spelling of 1028081664 in words is "one billion, twenty-eight million, eighty-one thousand, six hundred sixty-four".