1211001256800 has 360 divisors, whose sum is σ = 4430469853656. Its totient is φ = 321896540160.

The previous prime is 1211001256781. The next prime is 1211001256939. The reversal of 1211001256800 is 86521001121.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 20252547 + ... + 20312253.

Almost surely, 2^{1211001256800} is an apocalyptic number.

1211001256800 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 1211001256800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2215234926828).

1211001256800 is an abundant number, since it is smaller than the sum of its proper divisors (3219468596856).

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

1211001256800 is a wasteful number, since it uses less digits than its factorization.

1211001256800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60052 (or 60030 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 27.

Adding to 1211001256800 its reverse (86521001121), we get a palindrome (1297522257921).

The spelling of 1211001256800 in words is "one trillion, two hundred eleven billion, one million, two hundred fifty-six thousand, eight hundred".