55731517 has 4 divisors (see below), whose sum is σ = 55754656. Its totient is φ = 55708380.

The previous prime is 55731449. The next prime is 55731523. The reversal of 55731517 is 71513755.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71513755 = 5 ⋅14302751.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55731517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55731527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7473 + ... + 12934.

It is an arithmetic number, because the mean of its divisors is an integer number (13938664).

Almost surely, 2^55731517 is an apocalyptic number.

It is an amenable number.

55731517 is a deficient number, since it is larger than the sum of its proper divisors (23139).

55731517 is a wasteful number, since it uses less digits than its factorization.

55731517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23138.

The product of its digits is 18375, while the sum is 34.

The square root of 55731517 is about 7465.3544457045. The cubic root of 55731517 is about 381.9738407568.

The spelling of 55731517 in words is "fifty-five million, seven hundred thirty-one thousand, five hundred seventeen".