5551661601 has 6 divisors (see below), whose sum is σ = 8019066770. Its totient is φ = 3701107728.

The previous prime is 5551661561. The next prime is 5551661611. The reversal of 5551661601 is 1061661555.

It can be written as a sum of positive squares in only one way, i.e., 3602880576 + 1948781025 = 60024^2 + 44145^2 .

It is not a de Polignac number, because 5551661601 - 2¹⁰ = 5551660577 is a prime.

It is a super-3 number, since 3×5551661601³ (a number of 30 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5551661611) 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, 308425636 + ... + 308425653.

Almost surely, 2^5551661601 is an apocalyptic number.

It is an amenable number.

5551661601 is a deficient number, since it is larger than the sum of its proper divisors (2467405169).

5551661601 is a wasteful number, since it uses less digits than its factorization.

5551661601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 616851295 (or 616851292 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The square root of 5551661601 is about 74509.4732299189. The cubic root of 5551661601 is about 1770.6837241712.

The spelling of 5551661601 in words is "five billion, five hundred fifty-one million, six hundred sixty-one thousand, six hundred one".