55917287 has 4 divisors (see below), whose sum is σ = 56099736. Its totient is φ = 55734840.

The previous prime is 55917283. The next prime is 55917293. The reversal of 55917287 is 78271955.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78271955 = 5 ⋅15654391.

It is a cyclic number.

It is not a de Polignac number, because 55917287 - 2² = 55917283 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 (55917283) 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, 90764 + ... + 91377.

It is an arithmetic number, because the mean of its divisors is an integer number (14024934).

Almost surely, 2^55917287 is an apocalyptic number.

55917287 is a deficient number, since it is larger than the sum of its proper divisors (182449).

55917287 is a wasteful number, since it uses less digits than its factorization.

55917287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182448.

The product of its digits is 176400, while the sum is 44.

The square root of 55917287 is about 7477.7862365810. The cubic root of 55917287 is about 382.3977815057.

The spelling of 55917287 in words is "fifty-five million, nine hundred seventeen thousand, two hundred eighty-seven".