551981000 has 32 divisors (see below), whose sum is σ = 1291637880. Its totient is φ = 220792000.

The previous prime is 551980997. The next prime is 551981011. The reversal of 551981000 is 189155.

It can be written as a sum of positive squares in 4 ways, for example, as 289476196 + 262504804 = 17014^2 + 16202^2 .

It is a super-2 number, since 2×551981000² = 609366048722000000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 274991 + ... + 276990.

Almost surely, 2^551981000 is an apocalyptic number.

551981000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

551981000 is an abundant number, since it is smaller than the sum of its proper divisors (739656880).

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

551981000 is a wasteful number, since it uses less digits than its factorization.

551981000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552002 (or 551988 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 29.

The square root of 551981000 is about 23494.2758986099. The cubic root of 551981000 is about 820.3037740266.

The spelling of 551981000 in words is "five hundred fifty-one million, nine hundred eighty-one thousand".