55720100 has 18 divisors (see below), whose sum is σ = 120912834. Its totient is φ = 22288000.

The previous prime is 55720073. The next prime is 55720109. The reversal of 55720100 is 102755.

It can be written as a sum of positive squares in 3 ways, for example, as 128164 + 55591936 = 358^2 + 7456^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (55720109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 278501 + ... + 278700.

Almost surely, 2^55720100 is an apocalyptic number.

55720100 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

55720100 is an abundant number, since it is smaller than the sum of its proper divisors (65192734).

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

55720100 is a wasteful number, since it uses less digits than its factorization.

55720100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557215 (or 557208 counting only the distinct ones).

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 55720100 is about 7464.5897409034. The cubic root of 55720100 is about 381.9477556175.

Adding to 55720100 its reverse (102755), we get a palindrome (55822855).

The spelling of 55720100 in words is "fifty-five million, seven hundred twenty thousand, one hundred".