1200111021000 has 384 divisors, whose sum is σ = 4223161144800. Its totient is φ = 307108454400.

The previous prime is 1200111020987. The next prime is 1200111021019. The reversal of 1200111021000 is 1201110021.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 19919935044 + 1180191085956 = 141138^2 + 1086366^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 24284316 + ... + 24333684.

Almost surely, 2^{1200111021000} is an apocalyptic number.

1200111021000 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 1200111021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2111580572400).

1200111021000 is an abundant number, since it is smaller than the sum of its proper divisors (3023050123800).

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

1200111021000 is a wasteful number, since it uses less digits than its factorization.

1200111021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49506 (or 49489 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 1200111021000 its reverse (1201110021), we get a palindrome (1201312131021).

The spelling of 1200111021000 in words is "one trillion, two hundred billion, one hundred eleven million, twenty-one thousand".