1121380921 has 2 divisors, whose sum is σ = 1121380922. Its totient is φ = 1121380920.

The previous prime is 1121380919. The next prime is 1121380937. The reversal of 1121380921 is 1290831211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1119638521 + 1742400 = 33461^2 + 1320^2 .

It is a cyclic number.

It is not a de Polignac number, because 1121380921 - 2¹ = 1121380919 is a prime.

Together with 1121380919, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1121380921.

It is not a weakly prime, because it can be changed into another prime (1121380951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 560690460 + 560690461.

It is an arithmetic number, because the mean of its divisors is an integer number (560690461).

Almost surely, 2^1121380921 is an apocalyptic number.

It is an amenable number.

1121380921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1121380921 is an equidigital number, since it uses as much as digits as its factorization.

1121380921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 28.

The square root of 1121380921 is about 33487.0261593949. The cubic root of 1121380921 is about 1038.9254560371.

The spelling of 1121380921 in words is "one billion, one hundred twenty-one million, three hundred eighty thousand, nine hundred twenty-one".