1231501311144 has 128 divisors (see below), whose sum is σ = 3685973491200. Its totient is φ = 378718260480.

The previous prime is 1231501311143. The next prime is 1231501311221. The reversal of 1231501311144 is 4411131051321.

1231501311144 is a `hidden beast` number, since 1 + 2 + 3 + 1 + 501 + 3 + 11 + 144 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (1231501311143) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5107857 + ... + 5343519.

It is an arithmetic number, because the mean of its divisors is an integer number (28796667900).

Almost surely, 2^{1231501311144} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1231501311144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1842986745600).

1231501311144 is an abundant number, since it is smaller than the sum of its proper divisors (2454472180056).

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

1231501311144 is a wasteful number, since it uses less digits than its factorization.

1231501311144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237552 (or 237542 counting only the distinct ones).

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

Adding to 1231501311144 its reverse (4411131051321), we get a palindrome (5642632362465).

The spelling of 1231501311144 in words is "one trillion, two hundred thirty-one billion, five hundred one million, three hundred eleven thousand, one hundred forty-four".