53721505 has 4 divisors (see below), whose sum is σ = 64465812. Its totient is φ = 42977200.

The previous prime is 53721497. The next prime is 53721527. The reversal of 53721505 is 50512735.

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 29030544 + 24690961 = 5388^2 + 4969^2 .

It is not a de Polignac number, because 53721505 - 2³ = 53721497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5372146 + ... + 5372155.

It is an arithmetic number, because the mean of its divisors is an integer number (16116453).

Almost surely, 2^53721505 is an apocalyptic number.

It is an amenable number.

53721505 is a deficient number, since it is larger than the sum of its proper divisors (10744307).

53721505 is a wasteful number, since it uses less digits than its factorization.

53721505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10744306.

The product of its (nonzero) digits is 5250, while the sum is 28.

The square root of 53721505 is about 7329.4955488083. The cubic root of 53721505 is about 377.3254137656.

The spelling of 53721505 in words is "fifty-three million, seven hundred twenty-one thousand, five hundred five".