1661330 has 24 divisors (see below), whose sum is σ = 3289356. Its totient is φ = 603680.

The previous prime is 1661327. The next prime is 1661333. The reversal of 1661330 is 331661.

It is an interprime number because it is at equal distance from previous prime (1661327) and next prime (1661333).

It can be written as a sum of positive squares in 2 ways, for example, as 1545049 + 116281 = 1243^2 + 341^2 .

It is not an unprimeable number, because it can be changed into a prime (1661333) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 524 + ... + 1896.

2^1661330 is an apocalyptic number.

1661330 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1661330 is a deficient number, since it is larger than the sum of its proper divisors (1628026).

1661330 is a wasteful number, since it uses less digits than its factorization.

1661330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1402 (or 1391 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 1661330 is about 1288.9259094300. The cubic root of 1661330 is about 118.4364284822.

Adding to 1661330 its reverse (331661), we get a palindrome (1992991).

It can be divided in two parts, 1661 and 330, that added together give a palindrome (1991).

The spelling of 1661330 in words is "one million, six hundred sixty-one thousand, three hundred thirty".