1012021009 has 4 divisors (see below), whose sum is σ = 1044666880. Its totient is φ = 979375140.

The previous prime is 1012021001. The next prime is 1012021019. The reversal of 1012021009 is 9001202101.

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: 9001202101 = 19 ⋅473747479.

It is a cyclic number.

It is not a de Polignac number, because 1012021009 - 2³ = 1012021001 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1012020983 and 1012021001.

It is not an unprimeable number, because it can be changed into a prime (1012021001) 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, 16322889 + ... + 16322950.

It is an arithmetic number, because the mean of its divisors is an integer number (261166720).

Almost surely, 2^1012021009 is an apocalyptic number.

It is an amenable number.

1012021009 is a deficient number, since it is larger than the sum of its proper divisors (32645871).

1012021009 is an equidigital number, since it uses as much as digits as its factorization.

1012021009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32645870.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 1012021009 is about 31812.2776455883. The cubic root of 1012021009 is about 1003.9910533030.

The spelling of 1012021009 in words is "one billion, twelve million, twenty-one thousand, nine".