55172431 has 4 divisors (see below), whose sum is σ = 55246072. Its totient is φ = 55098792.

The previous prime is 55172419. The next prime is 55172441. The reversal of 55172431 is 13427155.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55172431 - 2⁵ = 55172399 is a prime.

It is a super-2 number, since 2×55172431² = 6087994284899522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55172431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55172441) 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, 35685 + ... + 37198.

It is an arithmetic number, because the mean of its divisors is an integer number (13811518).

Almost surely, 2^55172431 is an apocalyptic number.

55172431 is a deficient number, since it is larger than the sum of its proper divisors (73641).

55172431 is an equidigital number, since it uses as much as digits as its factorization.

55172431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73640.

The product of its digits is 4200, while the sum is 28.

The square root of 55172431 is about 7427.8146853567. The cubic root of 55172431 is about 380.6922538383.

Adding to 55172431 its reverse (13427155), we get a palindrome (68599586).

The spelling of 55172431 in words is "fifty-five million, one hundred seventy-two thousand, four hundred thirty-one".