1311123402 has 64 divisors (see below), whose sum is σ = 3131187840. Its totient is φ = 405174528.

The previous prime is 1311123391. The next prime is 1311123413. The reversal of 1311123402 is 2043211131.

1311123402 is a `hidden beast` number, since 1 + 311 + 12 + 340 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (1311123391) and next prime (1311123413).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50848 + ... + 72164.

It is an arithmetic number, because the mean of its divisors is an integer number (48924810).

Almost surely, 2^1311123402 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1311123402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1565593920).

1311123402 is an abundant number, since it is smaller than the sum of its proper divisors (1820064438).

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

1311123402 is a wasteful number, since it uses less digits than its factorization.

1311123402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21412 (or 21406 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 1311123402 is about 36209.4380238081. The cubic root of 1311123402 is about 1094.4968677483.

Adding to 1311123402 its reverse (2043211131), we get a palindrome (3354334533).

The spelling of 1311123402 in words is "one billion, three hundred eleven million, one hundred twenty-three thousand, four hundred two".