991662 has 24 divisors (see below), whose sum is σ = 2307816. Its totient is φ = 283248.

The previous prime is 991651. The next prime is 991663. The reversal of 991662 is 266199.

It is a happy number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991662.

It is not an unprimeable number, because it can be changed into a prime (991663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1393 + ... + 1980.

It is an arithmetic number, because the mean of its divisors is an integer number (96159).

2⁹⁹¹⁶⁶² is an apocalyptic number.

991662 is an abundant number, since it is smaller than the sum of its proper divisors (1316154).

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

991662 is a wasteful number, since it uses less digits than its factorization.

991662 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3392 (or 3385 counting only the distinct ones).

The product of its digits is 5832, while the sum is 33.

The square root of 991662 is about 995.8222732998. The cubic root of 991662 is about 99.7212905990.

It can be divided in two parts, 991 and 662, that added together give a triangular number (1653 = T₅₇).

The spelling of 991662 in words is "nine hundred ninety-one thousand, six hundred sixty-two".