53784021 has 4 divisors (see below), whose sum is σ = 71712032. Its totient is φ = 35856012.

The previous prime is 53784011. The next prime is 53784023. The reversal of 53784021 is 12048735.

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 not a de Polignac number, because 53784021 - 2⁶ = 53783957 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 53784021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53784023) 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, 8964001 + ... + 8964006.

It is an arithmetic number, because the mean of its divisors is an integer number (17928008).

Almost surely, 2^53784021 is an apocalyptic number.

It is an amenable number.

53784021 is a deficient number, since it is larger than the sum of its proper divisors (17928011).

53784021 is a wasteful number, since it uses less digits than its factorization.

53784021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17928010.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 53784021 is about 7333.7589952220. The cubic root of 53784021 is about 377.4717222214.

The spelling of 53784021 in words is "fifty-three million, seven hundred eighty-four thousand, twenty-one".