5551919666 has 4 divisors (see below), whose sum is σ = 8327879502. Its totient is φ = 2775959832.

The previous prime is 5551919663. The next prime is 5551919683. The reversal of 5551919666 is 6669191555.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 3279967441 + 2271952225 = 57271^2 + 47665^2 .

It is not an unprimeable number, because it can be changed into a prime (5551919663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1387979915 + ... + 1387979918.

Almost surely, 2^5551919666 is an apocalyptic number.

5551919666 is a deficient number, since it is larger than the sum of its proper divisors (2775959836).

5551919666 is a wasteful number, since it uses less digits than its factorization.

5551919666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2775959835.

The product of its digits is 2187000, while the sum is 53.

The square root of 5551919666 is about 74511.2049694541. The cubic root of 5551919666 is about 1770.7111600663.

The spelling of 5551919666 in words is "five billion, five hundred fifty-one million, nine hundred nineteen thousand, six hundred sixty-six".