551661605605 has 8 divisors (see below), whose sum is σ = 722175192864. Its totient is φ = 401208440400.

The previous prime is 551661605591. The next prime is 551661605609. The reversal of 551661605605 is 506506166155.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 551661605605 - 2³⁹ = 1905791717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551661605609) 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, 5015105451 + ... + 5015105560.

It is an arithmetic number, because the mean of its divisors is an integer number (90271899108).

Almost surely, 2^551661605605 is an apocalyptic number.

551661605605 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

551661605605 is a deficient number, since it is larger than the sum of its proper divisors (170513587259).

551661605605 is a wasteful number, since it uses less digits than its factorization.

551661605605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10030211027.

The product of its (nonzero) digits is 810000, while the sum is 46.

The spelling of 551661605605 in words is "five hundred fifty-one billion, six hundred sixty-one million, six hundred five thousand, six hundred five".