2012061661 has 4 divisors (see below), whose sum is σ = 2015489952. Its totient is φ = 2008633372.

The previous prime is 2012061659. The next prime is 2012061679. The reversal of 2012061661 is 1661602102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2012061661 - 2¹ = 2012061659 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2012061691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1713265 + ... + 1714438.

It is an arithmetic number, because the mean of its divisors is an integer number (503872488).

Almost surely, 2^2012061661 is an apocalyptic number.

It is an amenable number.

2012061661 is a deficient number, since it is larger than the sum of its proper divisors (3428291).

2012061661 is an equidigital number, since it uses as much as digits as its factorization.

2012061661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3428290.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 2012061661 is about 44856.0103107711. The cubic root of 2012061661 is about 1262.4487653750.

Adding to 2012061661 its reverse (1661602102), we get a palindrome (3673663763).

The spelling of 2012061661 in words is "two billion, twelve million, sixty-one thousand, six hundred sixty-one".