1311443988 has 24 divisors (see below), whose sum is σ = 3240038592. Its totient is φ = 411433344.

The previous prime is 1311443957. The next prime is 1311443993. The reversal of 1311443988 is 8893441131.

It is a happy number.

It is a super-2 number, since 2×1311443988² = 3439770667322688288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3214120 + ... + 3214527.

It is an arithmetic number, because the mean of its divisors is an integer number (135001608).

Almost surely, 2^1311443988 is an apocalyptic number.

It is an amenable number.

1311443988 is an abundant number, since it is smaller than the sum of its proper divisors (1928594604).

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

1311443988 is a wasteful number, since it uses less digits than its factorization.

1311443988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6428671 (or 6428669 counting only the distinct ones).

The product of its digits is 82944, while the sum is 42.

The square root of 1311443988 is about 36213.8645825049. The cubic root of 1311443988 is about 1094.5860665168.

The spelling of 1311443988 in words is "one billion, three hundred eleven million, four hundred forty-three thousand, nine hundred eighty-eight".