1531131021200 has 120 divisors (see below), whose sum is σ = 4025779777056. Its totient is φ = 554995584000.

The previous prime is 1531131021191. The next prime is 1531131021257. The reversal of 1531131021200 is 21201311351.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 821315 + ... + 1933085.

Almost surely, 2^{1531131021200} is an apocalyptic number.

1531131021200 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 1531131021200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2012889888528).

1531131021200 is an abundant number, since it is smaller than the sum of its proper divisors (2494648755856).

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

1531131021200 is a wasteful number, since it uses less digits than its factorization.

1531131021200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1112113 (or 1112102 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 20.

Adding to 1531131021200 its reverse (21201311351), we get a palindrome (1552332332551).

The spelling of 1531131021200 in words is "one trillion, five hundred thirty-one billion, one hundred thirty-one million, twenty-one thousand, two hundred".