661107 has 4 divisors (see below), whose sum is σ = 881480. Its totient is φ = 440736.

The previous prime is 661103. The next prime is 661109. The reversal of 661107 is 701166.

661107 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 661107 - 2² = 661103 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661103) 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, 110182 + ... + 110187.

It is an arithmetic number, because the mean of its divisors is an integer number (220370).

2⁶⁶¹¹⁰⁷ is an apocalyptic number.

661107 is a deficient number, since it is larger than the sum of its proper divisors (220373).

661107 is a wasteful number, since it uses less digits than its factorization.

661107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220372.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 661107 is about 813.0848664192. The cubic root of 661107 is about 87.1145274621.

The spelling of 661107 in words is "six hundred sixty-one thousand, one hundred seven".