1211531031144 has 224 divisors, whose sum is σ = 3930978522240. Its totient is φ = 342723312000.

The previous prime is 1211531031047. The next prime is 1211531031169. The reversal of 1211531031144 is 4411301351121.

1211531031144 is a `hidden beast` number, since 1 + 2 + 11 + 531 + 0 + 3 + 114 + 4 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 3976309 + ... + 4270139.

It is an arithmetic number, because the mean of its divisors is an integer number (17549011260).

Almost surely, 2^{1211531031144} is an apocalyptic number.

1211531031144 is a gapful number since it is divisible by the number (14) 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 1211531031144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1965489261120).

1211531031144 is an abundant number, since it is smaller than the sum of its proper divisors (2719447491096).

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

1211531031144 is a wasteful number, since it uses less digits than its factorization.

1211531031144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293963 (or 293944 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

Adding to 1211531031144 its reverse (4411301351121), we get a palindrome (5622832382265).

The spelling of 1211531031144 in words is "one trillion, two hundred eleven billion, five hundred thirty-one million, thirty-one thousand, one hundred forty-four".