991029 has 8 divisors (see below), whose sum is σ = 1423072. Its totient is φ = 609840.

The previous prime is 991027. The next prime is 991031. The reversal of 991029 is 920199.

It is an interprime number because it is at equal distance from previous prime (991027) and next prime (991031).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 991029 - 2¹ = 991027 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 990987 and 991005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12667 + ... + 12744.

It is an arithmetic number, because the mean of its divisors is an integer number (177884).

2⁹⁹¹⁰²⁹ is an apocalyptic number.

It is an amenable number.

991029 is a deficient number, since it is larger than the sum of its proper divisors (432043).

991029 is a wasteful number, since it uses less digits than its factorization.

991029 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25427.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 991029 is about 995.5043947668. The cubic root of 991029 is about 99.7000679739.

It can be divided in two parts, 99 and 1029, that added together give a triangular number (1128 = T₄₇).

The spelling of 991029 in words is "nine hundred ninety-one thousand, twenty-nine".