2051655655666 has 16 divisors (see below), whose sum is σ = 3240859406400. Its totient is φ = 971415957168.

The previous prime is 2051655655639. The next prime is 2051655655667. The reversal of 2051655655666 is 6665565561502.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 2051655655666.

It is not an unprimeable number, because it can be changed into a prime (2051655655667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11603670 + ... + 11779153.

It is an arithmetic number, because the mean of its divisors is an integer number (202553712900).

Almost surely, 2^{2051655655666} is an apocalyptic number.

2051655655666 is a deficient number, since it is larger than the sum of its proper divisors (1189203750734).

2051655655666 is a wasteful number, since it uses less digits than its factorization.

2051655655666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23385153.

The product of its (nonzero) digits is 48600000, while the sum is 58.

The spelling of 2051655655666 in words is "two trillion, fifty-one billion, six hundred fifty-five million, six hundred fifty-five thousand, six hundred sixty-six".