55405231 has 6 divisors (see below), whose sum is σ = 64451040. Its totient is φ = 47490156.

The previous prime is 55405223. The next prime is 55405247. The reversal of 55405231 is 13250455.

It is not a de Polignac number, because 55405231 - 2³ = 55405223 is a prime.

It is a super-2 number, since 2×55405231² = 6139479244326722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 55405196 and 55405205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55405291) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 565311 + ... + 565408.

It is an arithmetic number, because the mean of its divisors is an integer number (10741840).

Almost surely, 2^55405231 is an apocalyptic number.

55405231 is a deficient number, since it is larger than the sum of its proper divisors (9045809).

55405231 is a wasteful number, since it uses less digits than its factorization.

55405231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1130733 (or 1130726 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 55405231 is about 7443.4690165272. The cubic root of 55405231 is about 381.2269459857.

Adding to 55405231 its reverse (13250455), we get a palindrome (68655686).

The spelling of 55405231 in words is "fifty-five million, four hundred five thousand, two hundred thirty-one".