1640232320 has 128 divisors (see below), whose sum is σ = 4136140800. Its totient is φ = 621066240.

The previous prime is 1640232277. The next prime is 1640232337. The reversal of 1640232320 is 232320461.

1640232320 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 931601 + ... + 933359.

It is an arithmetic number, because the mean of its divisors is an integer number (32313600).

Almost surely, 2^1640232320 is an apocalyptic number.

1640232320 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 1640232320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2068070400).

1640232320 is an abundant number, since it is smaller than the sum of its proper divisors (2495908480).

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

1640232320 is a wasteful number, since it uses less digits than its factorization.

1640232320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1856 (or 1844 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 1640232320 is about 40499.7817278069. The cubic root of 1640232320 is about 1179.3293900941.

Adding to 1640232320 its reverse (232320461), we get a palindrome (1872552781).

The spelling of 1640232320 in words is "one billion, six hundred forty million, two hundred thirty-two thousand, three hundred twenty".