661676 has 12 divisors (see below), whose sum is σ = 1172472. Its totient is φ = 326688.

The previous prime is 661673. The next prime is 661679. The reversal of 661676 is 676166.

It is an interprime number because it is at equal distance from previous prime (661673) and next prime (661679).

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 661676.

It is not an unprimeable number, because it can be changed into a prime (661673) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 665 + ... + 1328.

It is an arithmetic number, because the mean of its divisors is an integer number (97706).

2⁶⁶¹⁶⁷⁶ is an apocalyptic number.

It is an amenable number.

661676 is a deficient number, since it is larger than the sum of its proper divisors (510796).

661676 is a wasteful number, since it uses less digits than its factorization.

661676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2080 (or 2078 counting only the distinct ones).

The product of its digits is 9072, while the sum is 32.

The square root of 661676 is about 813.4346931377. The cubic root of 661676 is about 87.1395128034.

The spelling of 661676 in words is "six hundred sixty-one thousand, six hundred seventy-six".