55217897 has 4 divisors (see below), whose sum is σ = 63106176. Its totient is φ = 47329620.

The previous prime is 55217893. The next prime is 55217927. The reversal of 55217897 is 79871255.

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.

It is a cyclic number.

It is not a de Polignac number, because 55217897 - 2² = 55217893 is a prime.

It is a super-2 number, since 2×55217897² = 6098032298205218, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55217893) 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, 3944129 + ... + 3944142.

It is an arithmetic number, because the mean of its divisors is an integer number (15776544).

Almost surely, 2^55217897 is an apocalyptic number.

It is an amenable number.

55217897 is a deficient number, since it is larger than the sum of its proper divisors (7888279).

55217897 is an equidigital number, since it uses as much as digits as its factorization.

55217897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7888278.

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

The square root of 55217897 is about 7430.8745784060. The cubic root of 55217897 is about 380.7967976076.

The spelling of 55217897 in words is "fifty-five million, two hundred seventeen thousand, eight hundred ninety-seven".