47131821 has 32 divisors (see below), whose sum is σ = 78249600. Its totient is φ = 27786240.

The previous prime is 47131817. The next prime is 47131823. The reversal of 47131821 is 12813174.

It is not a de Polignac number, because 47131821 - 2² = 47131817 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47131823) 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, 8845 + ... + 13133.

It is an arithmetic number, because the mean of its divisors is an integer number (2445300).

Almost surely, 2^47131821 is an apocalyptic number.

It is an amenable number.

47131821 is a deficient number, since it is larger than the sum of its proper divisors (31117779).

47131821 is a wasteful number, since it uses less digits than its factorization.

47131821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4346 (or 4340 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 47131821 is about 6865.2619032343. The cubic root of 47131821 is about 361.2196824850.

Adding to 47131821 its reverse (12813174), we get a palindrome (59944995).

The spelling of 47131821 in words is "forty-seven million, one hundred thirty-one thousand, eight hundred twenty-one".