551055561 has 32 divisors (see below), whose sum is σ = 895961088. Its totient is φ = 294078720.

The previous prime is 551055529. The next prime is 551055569. The reversal of 551055561 is 165550155.

It is not a de Polignac number, because 551055561 - 2⁵ = 551055529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (551055569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 40876 + ... + 52658.

It is an arithmetic number, because the mean of its divisors is an integer number (27998784).

Almost surely, 2^551055561 is an apocalyptic number.

551055561 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

551055561 is a deficient number, since it is larger than the sum of its proper divisors (344905527).

551055561 is a wasteful number, since it uses less digits than its factorization.

551055561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11941.

The product of its (nonzero) digits is 18750, while the sum is 33.

The square root of 551055561 is about 23474.5726478673. The cubic root of 551055561 is about 819.8450832668.

The spelling of 551055561 in words is "five hundred fifty-one million, fifty-five thousand, five hundred sixty-one".