991672 has 32 divisors (see below), whose sum is σ = 2073600. Its totient is φ = 440800.

The previous prime is 991663. The next prime is 991693. The reversal of 991672 is 276199.

991672 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5097 + ... + 5287.

It is an arithmetic number, because the mean of its divisors is an integer number (64800).

2⁹⁹¹⁶⁷² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1036800).

991672 is an abundant number, since it is smaller than the sum of its proper divisors (1081928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

991672 is a wasteful number, since it uses less digits than its factorization.

991672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 263 counting only the distinct ones).

The product of its digits is 6804, while the sum is 34.

The square root of 991672 is about 995.8272942634. The cubic root of 991672 is about 99.7216257971.

It can be divided in two parts, 99 and 1672, that added together give a palindrome (1771).

The spelling of 991672 in words is "nine hundred ninety-one thousand, six hundred seventy-two".