1121000021 has 4 divisors (see below), whose sum is σ = 1157161344. Its totient is φ = 1084838700.

The previous prime is 1121000011. The next prime is 1121000081. The reversal of 1121000021 is 1200001211.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1121000021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1120999972 and 1121000008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121000011) 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, 18080615 + ... + 18080676.

It is an arithmetic number, because the mean of its divisors is an integer number (289290336).

Almost surely, 2^1121000021 is an apocalyptic number.

It is an amenable number.

1121000021 is a deficient number, since it is larger than the sum of its proper divisors (36161323).

1121000021 is an equidigital number, since it uses as much as digits as its factorization.

1121000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36161322.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1121000021 is about 33481.3383991739. The cubic root of 1121000021 is about 1038.8078119452.

Adding to 1121000021 its reverse (1200001211), we get a palindrome (2321001232).

The spelling of 1121000021 in words is "one billion, one hundred twenty-one million, twenty-one", and thus it is an aban number.