1065688640 has 56 divisors (see below), whose sum is σ = 2561036280. Its totient is φ = 422350848.

The previous prime is 1065688633. The next prime is 1065688661. The reversal of 1065688640 is 468865601.

It can be written as a sum of positive squares in 4 ways, for example, as 67634176 + 998054464 = 8224^2 + 31592^2 .

It is a super-2 number, since 2×1065688640² = 2271384554850099200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1065688591 and 1065688600.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19604 + ... + 50156.

Almost surely, 2^1065688640 is an apocalyptic number.

1065688640 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 1065688640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1280518140).

1065688640 is an abundant number, since it is smaller than the sum of its proper divisors (1495347640).

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

1065688640 is a wasteful number, since it uses less digits than its factorization.

1065688640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30679 (or 30669 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 44.

The square root of 1065688640 is about 32644.8868890673. The cubic root of 1065688640 is about 1021.4335347581.

The spelling of 1065688640 in words is "one billion, sixty-five million, six hundred eighty-eight thousand, six hundred forty".