5511561666 has 32 divisors (see below), whose sum is σ = 11976128640. Its totient is φ = 1680854784.

The previous prime is 5511561623. The next prime is 5511561673. The reversal of 5511561666 is 6661651155.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 303846 + ... + 321473.

It is an arithmetic number, because the mean of its divisors is an integer number (374254020).

Almost surely, 2^5511561666 is an apocalyptic number.

5511561666 is an abundant number, since it is smaller than the sum of its proper divisors (6464566974).

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

5511561666 is a wasteful number, since it uses less digits than its factorization.

5511561666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625450.

The product of its digits is 162000, while the sum is 42.

The square root of 5511561666 is about 74239.8926858061. The cubic root of 5511561666 is about 1766.4101719393.

The spelling of 5511561666 in words is "five billion, five hundred eleven million, five hundred sixty-one thousand, six hundred sixty-six".