999989428 has 12 divisors (see below), whose sum is σ = 1751427972. Its totient is φ = 499581440.

The previous prime is 999989411. The next prime is 999989429. The reversal of 999989428 is 824989999.

999989428 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 616926244 + 383063184 = 24838^2 + 19572^2 .

It is a super-2 number, since 2×999989428² = 1999957712223534368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999989429) 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, 97843 + ... + 107578.

It is an arithmetic number, because the mean of its divisors is an integer number (145952331).

Almost surely, 2^999989428 is an apocalyptic number.

It is an amenable number.

999989428 is a deficient number, since it is larger than the sum of its proper divisors (751438544).

999989428 is a wasteful number, since it uses less digits than its factorization.

999989428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206642 (or 206640 counting only the distinct ones).

The product of its digits is 30233088, while the sum is 67.

The square root of 999989428 is about 31622.6094432449. The cubic root of 999989428 is about 999.9964759876.

The spelling of 999989428 in words is "nine hundred ninety-nine million, nine hundred eighty-nine thousand, four hundred twenty-eight".