4412131821 has 12 divisors (see below), whose sum is σ = 6391137948. Its totient is φ = 2933086464.

The previous prime is 4412131781. The next prime is 4412131847. The reversal of 4412131821 is 1281312144.

4412131821 is a `hidden beast` number, since 441 + 213 + 1 + 8 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3514829796 + 897302025 = 59286^2 + 29955^2 .

It is not a de Polignac number, because 4412131821 - 2⁹ = 4412131309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4412131421) 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, 691210 + ... + 697563.

It is an arithmetic number, because the mean of its divisors is an integer number (532594829).

Almost surely, 2^4412131821 is an apocalyptic number.

It is an amenable number.

4412131821 is a deficient number, since it is larger than the sum of its proper divisors (1979006127).

4412131821 is a wasteful number, since it uses less digits than its factorization.

4412131821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389132 (or 1389129 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 4412131821 is about 66423.8799002287. The cubic root of 4412131821 is about 1640.1471983930.

Adding to 4412131821 its reverse (1281312144), we get a palindrome (5693443965).

The spelling of 4412131821 in words is "four billion, four hundred twelve million, one hundred thirty-one thousand, eight hundred twenty-one".