2016642661 has 4 divisors (see below), whose sum is σ = 2199973824. Its totient is φ = 1833311500.

The previous prime is 2016642647. The next prime is 2016642673. The reversal of 2016642661 is 1662466102.

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 2016642661 - 2⁷ = 2016642533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2016642601) 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, 91665565 + ... + 91665586.

It is an arithmetic number, because the mean of its divisors is an integer number (549993456).

Almost surely, 2^2016642661 is an apocalyptic number.

It is an amenable number.

2016642661 is a deficient number, since it is larger than the sum of its proper divisors (183331163).

2016642661 is a wasteful number, since it uses less digits than its factorization.

2016642661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183331162.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 2016642661 is about 44907.0446700738. The cubic root of 2016642661 is about 1263.4061406527.

The spelling of 2016642661 in words is "two billion, sixteen million, six hundred forty-two thousand, six hundred sixty-one".