2066217661764 has 18 divisors (see below), whose sum is σ = 5222939089550. Its totient is φ = 688739220576.

The previous prime is 2066217661757. The next prime is 2066217661769. The reversal of 2066217661764 is 4671667126602.

2066217661764 is a `hidden beast` number, since 2 + 0 + 6 + 6 + 2 + 17 + 6 + 617 + 6 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1123298980164 + 942918681600 = 1059858^2 + 971040^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a self number, because there is not a number n which added to its sum of digits gives 2066217661764.

It is not an unprimeable number, because it can be changed into a prime (2066217661769) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28697467489 + ... + 28697467560.

Almost surely, 2^{2066217661764} is an apocalyptic number.

It is an amenable number.

2066217661764 is an abundant number, since it is smaller than the sum of its proper divisors (3156721427786).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2066217661764 is a wasteful number, since it uses less digits than its factorization.

2066217661764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57394935059 (or 57394935054 counting only the distinct ones).

The product of its (nonzero) digits is 6096384, while the sum is 54.

The spelling of 2066217661764 in words is "two trillion, sixty-six billion, two hundred seventeen million, six hundred sixty-one thousand, seven hundred sixty-four".