1211513388 has 12 divisors (see below), whose sum is σ = 2826864600. Its totient is φ = 403837792.

The previous prime is 1211513383. The next prime is 1211513417. The reversal of 1211513388 is 8833151121.

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

It is not an unprimeable number, because it can be changed into a prime (1211513383) 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, 50479713 + ... + 50479736.

It is an arithmetic number, because the mean of its divisors is an integer number (235572050).

Almost surely, 2^1211513388 is an apocalyptic number.

It is an amenable number.

1211513388 is an abundant number, since it is smaller than the sum of its proper divisors (1615351212).

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

1211513388 is a wasteful number, since it uses less digits than its factorization.

1211513388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100959456 (or 100959454 counting only the distinct ones).

The product of its digits is 5760, while the sum is 33.

The square root of 1211513388 is about 34806.8008871830. The cubic root of 1211513388 is about 1066.0463132858.

The spelling of 1211513388 in words is "one billion, two hundred eleven million, five hundred thirteen thousand, three hundred eighty-eight".