55121200 has 30 divisors (see below), whose sum is σ = 132429644. Its totient is φ = 22048320.

The previous prime is 55121159. The next prime is 55121201. The reversal of 55121200 is 212155.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (55121201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 68502 + ... + 69301.

Almost surely, 2^55121200 is an apocalyptic number.

55121200 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

55121200 is an abundant number, since it is smaller than the sum of its proper divisors (77308444).

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

55121200 is a wasteful number, since it uses less digits than its factorization.

55121200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137821 (or 137810 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 55121200 is about 7424.3652927372. The cubic root of 55121200 is about 380.5743852804.

Adding to 55121200 its reverse (212155), we get a palindrome (55333355).

The spelling of 55121200 in words is "fifty-five million, one hundred twenty-one thousand, two hundred".