551205551 has 4 divisors (see below), whose sum is σ = 593605992. Its totient is φ = 508805112.

The previous prime is 551205547. The next prime is 551205607. The reversal of 551205551 is 155502155.

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

It is a cyclic number.

It is not a de Polignac number, because 551205551 - 2² = 551205547 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 (551205521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21200201 + ... + 21200226.

It is an arithmetic number, because the mean of its divisors is an integer number (148401498).

Almost surely, 2^551205551 is an apocalyptic number.

551205551 is a deficient number, since it is larger than the sum of its proper divisors (42400441).

551205551 is a wasteful number, since it uses less digits than its factorization.

551205551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42400440.

The product of its (nonzero) digits is 6250, while the sum is 29.

The square root of 551205551 is about 23477.7671638510. The cubic root of 551205551 is about 819.9194601643.

The spelling of 551205551 in words is "five hundred fifty-one million, two hundred five thousand, five hundred fifty-one".