661595 has 16 divisors (see below), whose sum is σ = 905472. Its totient is φ = 459360.

The previous prime is 661553. The next prime is 661603. The reversal of 661595 is 595166.

It is not a de Polignac number, because 661595 - 2¹² = 657499 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1004 + ... + 1526.

It is an arithmetic number, because the mean of its divisors is an integer number (56592).

2⁶⁶¹⁵⁹⁵ is an apocalyptic number.

661595 is a deficient number, since it is larger than the sum of its proper divisors (243877).

661595 is a wasteful number, since it uses less digits than its factorization.

661595 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562.

The product of its digits is 8100, while the sum is 32.

The square root of 661595 is about 813.3849027367. The cubic root of 661595 is about 87.1359568895.

It can be divided in two parts, 66 and 1595, that added together give a palindrome (1661).

The spelling of 661595 in words is "six hundred sixty-one thousand, five hundred ninety-five".