1640712864 has 144 divisors (see below), whose sum is σ = 5067619200. Its totient is φ = 463389696.

The previous prime is 1640712847. The next prime is 1640712869. The reversal of 1640712864 is 4682170461.

It is not an unprimeable number, because it can be changed into a prime (1640712869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 416697 + ... + 420615.

It is an arithmetic number, because the mean of its divisors is an integer number (35191800).

Almost surely, 2^1640712864 is an apocalyptic number.

1640712864 is a gapful number since it is divisible by the number (14) 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 1640712864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2533809600).

1640712864 is an abundant number, since it is smaller than the sum of its proper divisors (3426906336).

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

1640712864 is a wasteful number, since it uses less digits than its factorization.

1640712864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4035 (or 4020 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 39.

The square root of 1640712864 is about 40505.7139672911. The cubic root of 1640712864 is about 1179.4445494570. Note that the first 3 decimals are identical.

The spelling of 1640712864 in words is "one billion, six hundred forty million, seven hundred twelve thousand, eight hundred sixty-four".