1991552 has 16 divisors (see below), whose sum is σ = 3967800. Its totient is φ = 995712.

The previous prime is 1991551. The next prime is 1991573. The reversal of 1991552 is 2551991.

It is a tau number, because it is divible by the number of its divisors (16).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7652 + ... + 7907.

2^1991552 is an apocalyptic number.

It is an amenable number.

1991552 is a deficient number, since it is larger than the sum of its proper divisors (1976248).

1991552 is an equidigital number, since it uses as much as digits as its factorization.

1991552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15573 (or 15561 counting only the distinct ones).

The product of its digits is 4050, while the sum is 32.

The square root of 1991552 is about 1411.2235825694. The cubic root of 1991552 is about 125.8144577431.

The spelling of 1991552 in words is "one million, nine hundred ninety-one thousand, five hundred fifty-two".