53257021 has 4 divisors (see below), whose sum is σ = 55093500. Its totient is φ = 51420544.

The previous prime is 53256989. The next prime is 53257081. The reversal of 53257021 is 12075235.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17388900 + 35868121 = 4170^2 + 5989^2 .

It is a cyclic number.

It is not a de Polignac number, because 53257021 - 2⁵ = 53256989 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 (53257081) 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, 918196 + ... + 918253.

It is an arithmetic number, because the mean of its divisors is an integer number (13773375).

Almost surely, 2^53257021 is an apocalyptic number.

It is an amenable number.

53257021 is a deficient number, since it is larger than the sum of its proper divisors (1836479).

53257021 is a wasteful number, since it uses less digits than its factorization.

53257021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836478.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 53257021 is about 7297.7408148002. The cubic root of 53257021 is about 376.2347942185.

The spelling of 53257021 in words is "fifty-three million, two hundred fifty-seven thousand, twenty-one".