11903115721 has 12 divisors (see below), whose sum is σ = 13848496788. Its totient is φ = 10201185792.

The previous prime is 11903115703. The next prime is 11903115727. The reversal of 11903115721 is 12751130911.

11903115721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 10337805625 + 1565310096 = 101675^2 + 39564^2 .

It is not a de Polignac number, because 11903115721 - 2⁵ = 11903115689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11903115727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 444505 + ... + 470521.

It is an arithmetic number, because the mean of its divisors is an integer number (1154041399).

Almost surely, 2^11903115721 is an apocalyptic number.

It is an amenable number.

11903115721 is a deficient number, since it is larger than the sum of its proper divisors (1945381067).

11903115721 is an equidigital number, since it uses as much as digits as its factorization.

11903115721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35368 (or 35361 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 31.

The spelling of 11903115721 in words is "eleven billion, nine hundred three million, one hundred fifteen thousand, seven hundred twenty-one".