1209347988 has 12 divisors (see below), whose sum is σ = 2821812000. Its totient is φ = 403115992.

The previous prime is 1209347983. The next prime is 1209347999. The reversal of 1209347988 is 8897439021.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 1209347988.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1209347983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50389488 + ... + 50389511.

It is an arithmetic number, because the mean of its divisors is an integer number (235151000).

Almost surely, 2^1209347988 is an apocalyptic number.

It is an amenable number.

1209347988 is an abundant number, since it is smaller than the sum of its proper divisors (1612464012).

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

1209347988 is a wasteful number, since it uses less digits than its factorization.

1209347988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100779006 (or 100779004 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 51.

The square root of 1209347988 is about 34775.6809854243. The cubic root of 1209347988 is about 1065.4108014281.

The spelling of 1209347988 in words is "one billion, two hundred nine million, three hundred forty-seven thousand, nine hundred eighty-eight".