1311540140 has 48 divisors (see below), whose sum is σ = 2920149792. Its totient is φ = 493095936.

The previous prime is 1311540137. The next prime is 1311540149. The reversal of 1311540140 is 410451131.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (1311540149) 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, 306254 + ... + 310506.

It is an arithmetic number, because the mean of its divisors is an integer number (60836454).

Almost surely, 2^1311540140 is an apocalyptic number.

1311540140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311540140 is an abundant number, since it is smaller than the sum of its proper divisors (1608609652).

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

1311540140 is a wasteful number, since it uses less digits than its factorization.

1311540140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5186 (or 5184 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 1311540140 is about 36215.1921160167. The cubic root of 1311540140 is about 1094.6128166915.

Adding to 1311540140 its reverse (410451131), we get a palindrome (1721991271).

The spelling of 1311540140 in words is "one billion, three hundred eleven million, five hundred forty thousand, one hundred forty".