1660631 has 4 divisors (see below), whose sum is σ = 1897872. Its totient is φ = 1423392.

The previous prime is 1660609. The next prime is 1660661. The reversal of 1660631 is 1360661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1360661 = 151 ⋅9011.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1660631 is a prime.

It is a super-2 number, since 2×1660631² = 5515390636322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1660597 and 1660606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660601) 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 3 ways as a sum of consecutive naturals, for example, 118610 + ... + 118623.

It is an arithmetic number, because the mean of its divisors is an integer number (474468).

2^1660631 is an apocalyptic number.

1660631 is a deficient number, since it is larger than the sum of its proper divisors (237241).

1660631 is an equidigital number, since it uses as much as digits as its factorization.

1660631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237240.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 1660631 is about 1288.6547248972. The cubic root of 1660631 is about 118.4198155522.

The spelling of 1660631 in words is "one million, six hundred sixty thousand, six hundred thirty-one".