105661509 has 8 divisors (see below), whose sum is σ = 140937792. Its totient is φ = 70413120.

The previous prime is 105661487. The next prime is 105661513. The reversal of 105661509 is 905166501.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 105661509 - 2¹⁷ = 105530437 is a prime.

It is a super-2 number, since 2×105661509² = 22328708968314162, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 105661509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105661519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4624 + ... + 15254.

It is an arithmetic number, because the mean of its divisors is an integer number (17617224).

Almost surely, 2^105661509 is an apocalyptic number.

It is an amenable number.

105661509 is a deficient number, since it is larger than the sum of its proper divisors (35276283).

105661509 is a wasteful number, since it uses less digits than its factorization.

105661509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13947.

The product of its (nonzero) digits is 8100, while the sum is 33.

The square root of 105661509 is about 10279.1784204770. The cubic root of 105661509 is about 472.7580539386.

The spelling of 105661509 in words is "one hundred five million, six hundred sixty-one thousand, five hundred nine".