1991632 has 10 divisors (see below), whose sum is σ = 3858818. Its totient is φ = 995808.

The previous prime is 1991623. The next prime is 1991641. The reversal of 1991632 is 2361991.

It is an interprime number because it is at equal distance from previous prime (1991623) and next prime (1991641).

It can be written as a sum of positive squares in only one way, i.e., 1915456 + 76176 = 1384^2 + 276^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1991594 and 1991603.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 62223 + ... + 62254.

2^1991632 is an apocalyptic number.

It is an amenable number.

1991632 is a deficient number, since it is larger than the sum of its proper divisors (1867186).

1991632 is a wasteful number, since it uses less digits than its factorization.

1991632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124485 (or 124479 counting only the distinct ones).

The product of its digits is 2916, while the sum is 31.

The square root of 1991632 is about 1411.2519264823. The cubic root of 1991632 is about 125.8161423625.

The spelling of 1991632 in words is "one million, nine hundred ninety-one thousand, six hundred thirty-two".