661316 has 12 divisors (see below), whose sum is σ = 1197420. Its totient is φ = 319200.

The previous prime is 661267. The next prime is 661321. The reversal of 661316 is 613166.

It can be written as a sum of positive squares in 2 ways, for example, as 462400 + 198916 = 680^2 + 446^2 .

It is a junction number, because it is equal to n+sod(n) for n = 661291 and 661300.

It is an unprimeable number.

661316 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2735 + ... + 2966.

It is an arithmetic number, because the mean of its divisors is an integer number (99785).

2⁶⁶¹³¹⁶ is an apocalyptic number.

It is an amenable number.

661316 is a deficient number, since it is larger than the sum of its proper divisors (536104).

661316 is a wasteful number, since it uses less digits than its factorization.

661316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5734 (or 5732 counting only the distinct ones).

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

The square root of 661316 is about 813.2133791324. The cubic root of 661316 is about 87.1237065198.

The spelling of 661316 in words is "six hundred sixty-one thousand, three hundred sixteen".