51653521 has 8 divisors (see below), whose sum is σ = 52559784. Its totient is φ = 50755200.

The previous prime is 51653513. The next prime is 51653579. The reversal of 51653521 is 12535615.

It can be written as a sum of positive squares in 4 ways, for example, as 24206400 + 27447121 = 4920^2 + 5239^2 .

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 51653521 - 2³ = 51653513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51653521.

It is not an unprimeable number, because it can be changed into a prime (51603521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11971 + ... + 15703.

It is an arithmetic number, because the mean of its divisors is an integer number (6569973).

Almost surely, 2^51653521 is an apocalyptic number.

It is an amenable number.

51653521 is a deficient number, since it is larger than the sum of its proper divisors (906263).

51653521 is a wasteful number, since it uses less digits than its factorization.

51653521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3971.

The product of its digits is 4500, while the sum is 28.

The square root of 51653521 is about 7187.0384025689. The cubic root of 51653521 is about 372.4202697095.

The spelling of 51653521 in words is "fifty-one million, six hundred fifty-three thousand, five hundred twenty-one".