52540721 has 8 divisors (see below), whose sum is σ = 55679400. Its totient is φ = 49490560.

The previous prime is 52540699. The next prime is 52540723. The reversal of 52540721 is 12704525.

It can be written as a sum of positive squares in 4 ways, for example, as 2640625 + 49900096 = 1625^2 + 7064^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-52540721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (52540723) 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, 20906 + ... + 23283.

It is an arithmetic number, because the mean of its divisors is an integer number (6959925).

Almost surely, 2^52540721 is an apocalyptic number.

It is an amenable number.

52540721 is a deficient number, since it is larger than the sum of its proper divisors (3138679).

52540721 is a wasteful number, since it uses less digits than its factorization.

52540721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44259.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 52540721 is about 7248.4978443813. The cubic root of 52540721 is about 374.5404052535.

The spelling of 52540721 in words is "fifty-two million, five hundred forty thousand, seven hundred twenty-one".