551661605604 has 36 divisors (see below), whose sum is σ = 1395646939596. Its totient is φ = 183733049088.

The previous prime is 551661605591. The next prime is 551661605609. The reversal of 551661605604 is 406506166155.

It can be written as a sum of positive squares in 2 ways, for example, as 239661160704 + 312000444900 = 489552^2 + 558570^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 551661605604.

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 11 ways as a sum of consecutive naturals, for example, 6379489 + ... + 6465384.

Almost surely, 2^551661605604 is an apocalyptic number.

It is an amenable number.

551661605604 is an abundant number, since it is smaller than the sum of its proper divisors (843985333992).

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

551661605604 is a wasteful number, since it uses less digits than its factorization.

551661605604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12846076 (or 12846071 counting only the distinct ones).

The product of its (nonzero) digits is 648000, while the sum is 45.

The spelling of 551661605604 in words is "five hundred fifty-one billion, six hundred sixty-one million, six hundred five thousand, six hundred four".