1316505780 has 144 divisors (see below), whose sum is σ = 4082891904. Its totient is φ = 343284480.

The previous prime is 1316505761. The next prime is 1316505781. The reversal of 1316505780 is 875056131.

1316505780 is a `hidden beast` number, since 1 + 31 + 6 + 50 + 578 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1316505781) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2086065 + ... + 2086695.

It is an arithmetic number, because the mean of its divisors is an integer number (28353416).

Almost surely, 2^1316505780 is an apocalyptic number.

1316505780 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 1316505780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2041445952).

1316505780 is an abundant number, since it is smaller than the sum of its proper divisors (2766386124).

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

1316505780 is a wasteful number, since it uses less digits than its factorization.

1316505780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 886 (or 881 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 1316505780 is about 36283.6847632652. The cubic root of 1316505780 is about 1095.9925197511.

The spelling of 1316505780 in words is "one billion, three hundred sixteen million, five hundred five thousand, seven hundred eighty".