1366781240 has 128 divisors (see below), whose sum is σ = 3458142720. Its totient is φ = 481958400.

The previous prime is 1366781237. The next prime is 1366781309. The reversal of 1366781240 is 421876631.

1366781240 = 9235² + 9236² + ... + 9250².

It is a super-3 number, since 3×1366781240³ (a number of 28 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1366781194 and 1366781203.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2092754 + ... + 2093406.

It is an arithmetic number, because the mean of its divisors is an integer number (27016740).

Almost surely, 2^1366781240 is an apocalyptic number.

1366781240 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 1366781240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1729071360).

1366781240 is an abundant number, since it is smaller than the sum of its proper divisors (2091361480).

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

1366781240 is a wasteful number, since it uses less digits than its factorization.

1366781240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 813 (or 809 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 1366781240 is about 36970.0045983227. The cubic root of 1366781240 is about 1109.7700576099.

The spelling of 1366781240 in words is "one billion, three hundred sixty-six million, seven hundred eighty-one thousand, two hundred forty".