1661427 has 12 divisors (see below), whose sum is σ = 2541240. Its totient is φ = 1042368.

The previous prime is 1661353. The next prime is 1661431. The reversal of 1661427 is 7241661.

It is not a de Polignac number, because 1661427 - 2¹⁸ = 1399283 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1661427.

It is not an unprimeable number, because it can be changed into a prime (1661437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5277 + ... + 5582.

It is an arithmetic number, because the mean of its divisors is an integer number (211770).

2^1661427 is an apocalyptic number.

1661427 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1661427 is a deficient number, since it is larger than the sum of its proper divisors (879813).

1661427 is a wasteful number, since it uses less digits than its factorization.

1661427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10882 (or 10879 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 1661427 is about 1288.9635371103. The cubic root of 1661427 is about 118.4387334848.

It can be divided in two parts, 16614 and 27, that added together give a square (16641 = 129²).

The spelling of 1661427 in words is "one million, six hundred sixty-one thousand, four hundred twenty-seven".