53721421 has 8 divisors (see below), whose sum is σ = 58239104. Its totient is φ = 49258800.

The previous prime is 53721403. The next prime is 53721431. The reversal of 53721421 is 12412735.

It is a happy number.

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 53721421 - 2⁷ = 53721293 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 (53721431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11721 + ... + 15646.

It is an arithmetic number, because the mean of its divisors is an integer number (7279888).

Almost surely, 2^53721421 is an apocalyptic number.

It is an amenable number.

53721421 is a deficient number, since it is larger than the sum of its proper divisors (4517683).

53721421 is a wasteful number, since it uses less digits than its factorization.

53721421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27531.

The product of its digits is 1680, while the sum is 25.

The square root of 53721421 is about 7329.4898185344. The cubic root of 53721421 is about 377.3252171011.

The spelling of 53721421 in words is "fifty-three million, seven hundred twenty-one thousand, four hundred twenty-one".