1991946 has 16 divisors (see below), whose sum is σ = 4346208. Its totient is φ = 603600.

The previous prime is 1991933. The next prime is 1991947. The reversal of 1991946 is 6491991.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1991947) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15025 + ... + 15156.

It is an arithmetic number, because the mean of its divisors is an integer number (271638).

2^1991946 is an apocalyptic number.

1991946 is an abundant number, since it is smaller than the sum of its proper divisors (2354262).

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

1991946 is a wasteful number, since it uses less digits than its factorization.

1991946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30197.

The product of its digits is 17496, while the sum is 39.

The square root of 1991946 is about 1411.3631708387. The cubic root of 1991946 is about 125.8227540580.

It can be divided in two parts, 199 and 1946, that added together give a triangular number (2145 = T₆₅).

The spelling of 1991946 in words is "one million, nine hundred ninety-one thousand, nine hundred forty-six".