47042821 has 4 divisors (see below), whose sum is σ = 53763232. Its totient is φ = 40322412.

The previous prime is 47042813. The next prime is 47042837. The reversal of 47042821 is 12824074.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 47042821 - 2³ = 47042813 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 47042821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47042861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3360195 + ... + 3360208.

It is an arithmetic number, because the mean of its divisors is an integer number (13440808).

Almost surely, 2^47042821 is an apocalyptic number.

It is an amenable number.

47042821 is a deficient number, since it is larger than the sum of its proper divisors (6720411).

47042821 is an equidigital number, since it uses as much as digits as its factorization.

47042821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6720410.

The product of its (nonzero) digits is 3584, while the sum is 28.

The square root of 47042821 is about 6858.7769317860. The cubic root of 47042821 is about 360.9921730027.

Adding to 47042821 its reverse (12824074), we get a palindrome (59866895).

The spelling of 47042821 in words is "forty-seven million, forty-two thousand, eight hundred twenty-one".