551661056 has 40 divisors (see below), whose sum is σ = 1104398064. Its totient is φ = 275292160.

The previous prime is 551661053. The next prime is 551661059. The reversal of 551661056 is 650166155.

It is an interprime number because it is at equal distance from previous prime (551661053) and next prime (551661059).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551661053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 450461 + ... + 451683.

Almost surely, 2^551661056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 551661056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (552199032).

551661056 is an abundant number, since it is smaller than the sum of its proper divisors (552737008).

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

551661056 is an equidigital number, since it uses as much as digits as its factorization.

551661056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2122 (or 2106 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 35.

The square root of 551661056 is about 23487.4659339827. The cubic root of 551661056 is about 820.1452528727.

The spelling of 551661056 in words is "five hundred fifty-one million, six hundred sixty-one thousand, fifty-six".