53421821 has 8 divisors (see below), whose sum is σ = 55157304. Its totient is φ = 51701760.

The previous prime is 53421763. The next prime is 53421833. The reversal of 53421821 is 12812435.

It can be written as a sum of positive squares in 4 ways, for example, as 21724921 + 31696900 = 4661^2 + 5630^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 53421821 - 2⁶ = 53421757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53424821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3401 + ... + 10881.

It is an arithmetic number, because the mean of its divisors is an integer number (6894663).

Almost surely, 2^53421821 is an apocalyptic number.

It is an amenable number.

53421821 is a deficient number, since it is larger than the sum of its proper divisors (1735483).

53421821 is a wasteful number, since it uses less digits than its factorization.

53421821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7711.

The product of its digits is 1920, while the sum is 26.

The square root of 53421821 is about 7309.0232589588. The cubic root of 53421821 is about 376.6224717337.

The spelling of 53421821 in words is "fifty-three million, four hundred twenty-one thousand, eight hundred twenty-one".