55381000 has 32 divisors (see below), whose sum is σ = 129593880. Its totient is φ = 22152000.

The previous prime is 55380979. The next prime is 55381009. The reversal of 55381000 is 18355.

It can be written as a sum of positive squares in 4 ways, for example, as 31741956 + 23639044 = 5634^2 + 4862^2 .

It is a super-2 number, since 2×55381000² = 6134110322000000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55381009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26691 + ... + 28690.

Almost surely, 2^55381000 is an apocalyptic number.

55381000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

55381000 is an abundant number, since it is smaller than the sum of its proper divisors (74212880).

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

55381000 is a wasteful number, since it uses less digits than its factorization.

55381000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55402 (or 55388 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 55381000 is about 7441.8411700331. The cubic root of 55381000 is about 381.1713624428.

Adding to 55381000 its reverse (18355), we get a palindrome (55399355).

The spelling of 55381000 in words is "fifty-five million, three hundred eighty-one thousand".