1661056101 has 12 divisors (see below), whose sum is σ = 2399686380. Its totient is φ = 1107193920.

The previous prime is 1661056099. The next prime is 1661056141. The reversal of 1661056101 is 1016501661.

It can be written as a sum of positive squares in 2 ways, for example, as 1578155076 + 82901025 = 39726^2 + 9105^2 .

It is not a de Polignac number, because 1661056101 - 2¹ = 1661056099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661056141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 71041 + ... + 91481.

It is an arithmetic number, because the mean of its divisors is an integer number (199973865).

Almost surely, 2^1661056101 is an apocalyptic number.

It is an amenable number.

1661056101 is a deficient number, since it is larger than the sum of its proper divisors (738630279).

1661056101 is a wasteful number, since it uses less digits than its factorization.

1661056101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29476 (or 29473 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 1661056101 is about 40756.0560039855. The cubic root of 1661056101 is about 1184.2991935951.

Adding to 1661056101 its reverse (1016501661), we get a palindrome (2677557762).

The spelling of 1661056101 in words is "one billion, six hundred sixty-one million, fifty-six thousand, one hundred one".