1661313105 has 16 divisors (see below), whose sum is σ = 2953445760. Its totient is φ = 886033584.

The previous prime is 1661313103. The next prime is 1661313107. The reversal of 1661313105 is 5013131661.

1661313105 is a `hidden beast` number, since 16 + 613 + 1 + 31 + 0 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (1661313103) and next prime (1661313107).

It is not a de Polignac number, because 1661313105 - 2¹ = 1661313103 is a prime.

It is a super-2 number, since 2×1661313105² = 5519922465689482050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1661313103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6152877 + ... + 6153146.

It is an arithmetic number, because the mean of its divisors is an integer number (184590360).

Almost surely, 2^1661313105 is an apocalyptic number.

1661313105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1661313105 is a deficient number, since it is larger than the sum of its proper divisors (1292132655).

1661313105 is a wasteful number, since it uses less digits than its factorization.

1661313105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12306037 (or 12306031 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 1661313105 is about 40759.2088367770. The cubic root of 1661313105 is about 1184.3602699857.

Adding to 1661313105 its reverse (5013131661), we get a palindrome (6674444766).

The spelling of 1661313105 in words is "one billion, six hundred sixty-one million, three hundred thirteen thousand, one hundred five".