55087513 has 4 divisors (see below), whose sum is σ = 59325028. Its totient is φ = 50850000.

The previous prime is 55087471. The next prime is 55087519. The reversal of 55087513 is 31578055.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31578055 = 5 ⋅6315611.

It can be written as a sum of positive squares in 2 ways, for example, as 10291264 + 44796249 = 3208^2 + 6693^2 .

It is a cyclic number.

It is not a de Polignac number, because 55087513 - 2²¹ = 52990361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55087519) 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 3 ways as a sum of consecutive naturals, for example, 2118738 + ... + 2118763.

It is an arithmetic number, because the mean of its divisors is an integer number (14831257).

Almost surely, 2^55087513 is an apocalyptic number.

It is an amenable number.

55087513 is a deficient number, since it is larger than the sum of its proper divisors (4237515).

55087513 is a wasteful number, since it uses less digits than its factorization.

55087513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4237514.

The product of its (nonzero) digits is 21000, while the sum is 34.

The square root of 55087513 is about 7422.0962672280. The cubic root of 55087513 is about 380.4968408758.

The spelling of 55087513 in words is "fifty-five million, eighty-seven thousand, five hundred thirteen".