1111001921 has 2 divisors, whose sum is σ = 1111001922. Its totient is φ = 1111001920.

The previous prime is 1111001869. The next prime is 1111001929. The reversal of 1111001921 is 1291001111.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1065304321 + 45697600 = 32639^2 + 6760^2 .

It is an emirp because it is prime and its reverse (1291001111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1111001921 - 2²⁶ = 1043893057 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1111001921.

It is not a weakly prime, because it can be changed into another prime (1111001929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 555500960 + 555500961.

It is an arithmetic number, because the mean of its divisors is an integer number (555500961).

Almost surely, 2^1111001921 is an apocalyptic number.

It is an amenable number.

1111001921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1111001921 is an equidigital number, since it uses as much as digits as its factorization.

1111001921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 17.

The square root of 1111001921 is about 33331.6954414263. The cubic root of 1111001921 is about 1035.7102396336.

The spelling of 1111001921 in words is "one billion, one hundred eleven million, one thousand, nine hundred twenty-one".