551778018 has 64 divisors (see below), whose sum is σ = 1233677952. Its totient is φ = 163105280.

The previous prime is 551778013. The next prime is 551778023. The reversal of 551778018 is 810877155.

551778018 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (551778013) and next prime (551778023).

It is a super-2 number, since 2×551778018² = 608917962296016648, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (551778013) 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, 814696 + ... + 815372.

It is an arithmetic number, because the mean of its divisors is an integer number (19276218).

Almost surely, 2^551778018 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 551778018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (616838976).

551778018 is an abundant number, since it is smaller than the sum of its proper divisors (681899934).

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

551778018 is a wasteful number, since it uses less digits than its factorization.

551778018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 979.

The product of its (nonzero) digits is 78400, while the sum is 42.

The square root of 551778018 is about 23489.9556832277. The cubic root of 551778018 is about 820.2032105924.

The spelling of 551778018 in words is "five hundred fifty-one million, seven hundred seventy-eight thousand, eighteen".