1311778650 has 192 divisors, whose sum is σ = 4240228608. Its totient is φ = 260444160.

The previous prime is 1311778613. The next prime is 1311778669. The reversal of 1311778650 is 568771131.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1311778599 and 1311778608.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 229224 + ... + 234876.

It is an arithmetic number, because the mean of its divisors is an integer number (22084524).

Almost surely, 2^1311778650 is an apocalyptic number.

1311778650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1311778650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2120114304).

1311778650 is an abundant number, since it is smaller than the sum of its proper divisors (2928449958).

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

1311778650 is a wasteful number, since it uses less digits than its factorization.

1311778650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5705 (or 5700 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 39.

The square root of 1311778650 is about 36218.4849213768. The cubic root of 1311778650 is about 1094.6791662375.

The spelling of 1311778650 in words is "one billion, three hundred eleven million, seven hundred seventy-eight thousand, six hundred fifty".