1212656500 has 192 divisors, whose sum is σ = 3047466240. Its totient is φ = 417600000.

The previous prime is 1212656429. The next prime is 1212656503. The reversal of 1212656500 is 56562121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212656503) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12006450 + ... + 12006550.

It is an arithmetic number, because the mean of its divisors is an integer number (15872220).

Almost surely, 2^1212656500 is an apocalyptic number.

1212656500 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 1212656500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1523733120).

1212656500 is an abundant number, since it is smaller than the sum of its proper divisors (1834809740).

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

1212656500 is a wasteful number, since it uses less digits than its factorization.

1212656500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 1212656500 is about 34823.2178294884. The cubic root of 1212656500 is about 1066.3814938615.

It can be divided in two parts, 121265 and 6500, that added together give a triangular number (127765 = T₅₀₅).

The spelling of 1212656500 in words is "one billion, two hundred twelve million, six hundred fifty-six thousand, five hundred".