Search a number
-
+
661661 = 71113661
BaseRepresentation
bin10100001100010011101
31020121121222
42201202131
5132133121
622103125
75424020
oct2414235
91217558
10661661
11412130
1227aaa5
131a2220
141331b7
15d10ab
hexa189d

661661 has 16 divisors (see below), whose sum is σ = 889728. Its totient is φ = 475200.

The previous prime is 661621. The next prime is 661663. The reversal of 661661 is 166166.

It is a de Polignac number, because none of the positive numbers 2k-661661 is a prime.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 671 + ... + 1331.

It is an arithmetic number, because the mean of its divisors is an integer number (55608).

2661661 is an apocalyptic number.

It is an amenable number.

661661 is a deficient number, since it is larger than the sum of its proper divisors (228067).

661661 is a wasteful number, since it uses less digits than its factorization.

661661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692.

The product of its digits is 1296, while the sum is 26.

The square root of 661661 is about 813.4254729230. The cubic root of 661661 is about 87.1388543227.

The spelling of 661661 in words is "six hundred sixty-one thousand, six hundred sixty-one".

Divisors: 1 7 11 13 77 91 143 661 1001 4627 7271 8593 50897 60151 94523 661661