131200821 has 12 divisors (see below), whose sum is σ = 190496748. Its totient is φ = 87012864.

The previous prime is 131200801. The next prime is 131200841. The reversal of 131200821 is 128002131.

It is an interprime number because it is at equal distance from previous prime (131200801) and next prime (131200841).

It can be written as a sum of positive squares in 2 ways, for example, as 59120721 + 72080100 = 7689^2 + 8490^2 .

It is not a de Polignac number, because 131200821 - 2⁵ = 131200789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131200794 and 131200803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131200801) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36030 + ... + 39503.

It is an arithmetic number, because the mean of its divisors is an integer number (15874729).

Almost surely, 2^131200821 is an apocalyptic number.

It is an amenable number.

131200821 is a deficient number, since it is larger than the sum of its proper divisors (59295927).

131200821 is a wasteful number, since it uses less digits than its factorization.

131200821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75732 (or 75729 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 131200821 is about 11454.2926887696. The cubic root of 131200821 is about 508.1346970095.

Adding to 131200821 its reverse (128002131), we get a palindrome (259202952).

The spelling of 131200821 in words is "one hundred thirty-one million, two hundred thousand, eight hundred twenty-one".