661936 has 20 divisors (see below), whose sum is σ = 1399464. Its totient is φ = 300800.

The previous prime is 661931. The next prime is 661939. The reversal of 661936 is 639166.

It is a junction number, because it is equal to n+sod(n) for n = 661898 and 661907.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 661936.

It is not an unprimeable number, because it can be changed into a prime (661931) 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, 1705 + ... + 2056.

2⁶⁶¹⁹³⁶ is an apocalyptic number.

It is an amenable number.

661936 is an abundant number, since it is smaller than the sum of its proper divisors (737528).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661936 is a wasteful number, since it uses less digits than its factorization.

661936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3780 (or 3774 counting only the distinct ones).

The product of its digits is 5832, while the sum is 31.

The square root of 661936 is about 813.5944935900. The cubic root of 661936 is about 87.1509248875.

It can be divided in two parts, 66 and 1936, that added together give a palindrome (2002).

The spelling of 661936 in words is "six hundred sixty-one thousand, nine hundred thirty-six".