4006661081665 has 32 divisors (see below), whose sum is σ = 5521811005440. Its totient is φ = 2760235128000.

The previous prime is 4006661081651. The next prime is 4006661081701. The reversal of 4006661081665 is 5661801666004.

4006661081665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 4006661081665 - 2³¹ = 4004513598017 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8535840 + ... + 8992990.

It is an arithmetic number, because the mean of its divisors is an integer number (172556593920).

Almost surely, 2^{4006661081665} is an apocalyptic number.

It is an amenable number.

4006661081665 is a deficient number, since it is larger than the sum of its proper divisors (1515149923775).

4006661081665 is a wasteful number, since it uses less digits than its factorization.

4006661081665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465573.

The product of its (nonzero) digits is 1244160, while the sum is 49.

The spelling of 4006661081665 in words is "four trillion, six billion, six hundred sixty-one million, eighty-one thousand, six hundred sixty-five".