55509431 has 8 divisors (see below), whose sum is σ = 59790720. Its totient is φ = 51364152.

The previous prime is 55509427. The next prime is 55509463. The reversal of 55509431 is 13490555.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 55509431 - 2² = 55509427 is a prime.

It is a super-2 number, since 2×55509431² = 6162593859887522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55509401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33155 + ... + 34788.

It is an arithmetic number, because the mean of its divisors is an integer number (7473840).

Almost surely, 2^55509431 is an apocalyptic number.

55509431 is a deficient number, since it is larger than the sum of its proper divisors (4281289).

55509431 is a wasteful number, since it uses less digits than its factorization.

55509431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68005.

The product of its (nonzero) digits is 13500, while the sum is 32.

The square root of 55509431 is about 7450.4651532639. The cubic root of 55509431 is about 381.4657860754.

Adding to 55509431 its reverse (13490555), we get a palindrome (68999986).

The spelling of 55509431 in words is "fifty-five million, five hundred nine thousand, four hundred thirty-one".