1313636478 has 128 divisors (see below), whose sum is σ = 3651194880. Its totient is φ = 304197120.

The previous prime is 1313636453. The next prime is 1313636479. The reversal of 1313636478 is 8746363131.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1313636479) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 144825 + ... + 153627.

It is an arithmetic number, because the mean of its divisors is an integer number (28524960).

Almost surely, 2^1313636478 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1313636478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1825597440).

1313636478 is an abundant number, since it is smaller than the sum of its proper divisors (2337558402).

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

1313636478 is a wasteful number, since it uses less digits than its factorization.

1313636478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8862.

The product of its digits is 217728, while the sum is 42.

The square root of 1313636478 is about 36244.1233581390. The cubic root of 1313636478 is about 1095.1957082272.

The spelling of 1313636478 in words is "one billion, three hundred thirteen million, six hundred thirty-six thousand, four hundred seventy-eight".