52505721 has 36 divisors (see below), whose sum is σ = 82154800. Its totient is φ = 32222448.

The previous prime is 52505681. The next prime is 52505731. The reversal of 52505721 is 12750525.

It is a happy number.

It is not a de Polignac number, because 52505721 - 2⁹ = 52505209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (52505731) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 377670 + ... + 377808.

Almost surely, 2^52505721 is an apocalyptic number.

It is an amenable number.

52505721 is a deficient number, since it is larger than the sum of its proper divisors (29649079).

52505721 is a wasteful number, since it uses less digits than its factorization.

52505721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 52505721 is about 7246.0831488467. The cubic root of 52505721 is about 374.4572200856.

The spelling of 52505721 in words is "fifty-two million, five hundred five thousand, seven hundred twenty-one".