1200055500 has 576 divisors, whose sum is σ = 4808014848. Its totient is φ = 255052800.

The previous prime is 1200055469. The next prime is 1200055513. The reversal of 1200055500 is 55500021.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 14458459 + ... + 14458541.

It is an arithmetic number, because the mean of its divisors is an integer number (8347248).

Almost surely, 2^1200055500 is an apocalyptic number.

1200055500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1200055500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2404007424).

1200055500 is an abundant number, since it is smaller than the sum of its proper divisors (3607959348).

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

1200055500 is a wasteful number, since it uses less digits than its factorization.

1200055500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 18.

The square root of 1200055500 is about 34641.8172156138. The cubic root of 1200055500 is about 1062.6749515830.

Adding to 1200055500 its reverse (55500021), we get a palindrome (1255555521).

The spelling of 1200055500 in words is "one billion, two hundred million, fifty-five thousand, five hundred".