1011121009 has 4 divisors (see below), whose sum is σ = 1055082816. Its totient is φ = 967159204.

The previous prime is 1011120997. The next prime is 1011121021. The reversal of 1011121009 is 9001211101.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9001211101 = 293 ⋅30720857.

It is an interprime number because it is at equal distance from previous prime (1011120997) and next prime (1011121021).

It is a cyclic number.

It is not a de Polignac number, because 1011121009 - 2⁷ = 1011120881 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011120983 and 1011121001.

It is not an unprimeable number, because it can be changed into a prime (1011125009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21980869 + ... + 21980914.

It is an arithmetic number, because the mean of its divisors is an integer number (263770704).

Almost surely, 2^1011121009 is an apocalyptic number.

It is an amenable number.

1011121009 is a deficient number, since it is larger than the sum of its proper divisors (43961807).

1011121009 is an equidigital number, since it uses as much as digits as its factorization.

1011121009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43961806.

The product of its (nonzero) digits is 18, while the sum is 16.

The square root of 1011121009 is about 31798.1290172865. The cubic root of 1011121009 is about 1003.6933454063.

The spelling of 1011121009 in words is "one billion, eleven million, one hundred twenty-one thousand, nine".