1020011989 has 4 divisors (see below), whose sum is σ = 1025710560. Its totient is φ = 1014313420.

The previous prime is 1020011959. The next prime is 1020011999. The reversal of 1020011989 is 9891100201.

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 not a de Polignac number, because 1020011989 - 2⁵ = 1020011957 is a prime.

It is a super-2 number, since 2×1020011989² = 2080848915407472242, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1020011989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020011929) 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, 2849017 + ... + 2849374.

It is an arithmetic number, because the mean of its divisors is an integer number (256427640).

Almost surely, 2^1020011989 is an apocalyptic number.

It is an amenable number.

1020011989 is a deficient number, since it is larger than the sum of its proper divisors (5698571).

1020011989 is an equidigital number, since it uses as much as digits as its factorization.

1020011989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5698570.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 1020011989 is about 31937.6265398667. The cubic root of 1020011989 is about 1006.6266534661.

The spelling of 1020011989 in words is "one billion, twenty million, eleven thousand, nine hundred eighty-nine".