1012020009 has 64 divisors (see below), whose sum is σ = 1907189760. Its totient is φ = 459717120.

The previous prime is 1012019993. The next prime is 1012020019. The reversal of 1012020009 is 9000202101.

It is a happy number.

It is not a de Polignac number, because 1012020009 - 2⁴ = 1012019993 is a 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 1012020009.

It is not an unprimeable number, because it can be changed into a prime (1012020019) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 48189 + ... + 65925.

It is an arithmetic number, because the mean of its divisors is an integer number (29799840).

Almost surely, 2^1012020009 is an apocalyptic number.

1012020009 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1012020009 is a deficient number, since it is larger than the sum of its proper divisors (895169751).

1012020009 is a wasteful number, since it uses less digits than its factorization.

1012020009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17790.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1012020009 is about 31812.2619283823. The cubic root of 1012020009 is about 1003.9907226144.

The spelling of 1012020009 in words is "one billion, twelve million, twenty thousand, nine".