1316561664 has 144 divisors (see below), whose sum is σ = 3862865664. Its totient is φ = 394752000.

The previous prime is 1316561657. The next prime is 1316561669. The reversal of 1316561664 is 4661656131.

It is a super-2 number, since 2×1316561664² = 3466669230228897792, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1316561669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 852477 + ... + 854019.

It is an arithmetic number, because the mean of its divisors is an integer number (26825456).

Almost surely, 2^1316561664 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 1316561664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1931432832).

1316561664 is an abundant number, since it is smaller than the sum of its proper divisors (2546304000).

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

1316561664 is a wasteful number, since it uses less digits than its factorization.

1316561664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1674 (or 1660 counting only the distinct ones).

The product of its digits is 77760, while the sum is 39.

The square root of 1316561664 is about 36284.4548532839. The cubic root of 1316561664 is about 1096.0080273623.

The spelling of 1316561664 in words is "one billion, three hundred sixteen million, five hundred sixty-one thousand, six hundred sixty-four".