55138903 has 4 divisors (see below), whose sum is σ = 55154088. Its totient is φ = 55123720.

The previous prime is 55138901. The next prime is 55138907. The reversal of 55138903 is 30983155.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 55138903 - 2¹ = 55138901 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 (55138901) 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, 1425 + ... + 10597.

It is an arithmetic number, because the mean of its divisors is an integer number (13788522).

Almost surely, 2^55138903 is an apocalyptic number.

55138903 is a deficient number, since it is larger than the sum of its proper divisors (15185).

55138903 is an equidigital number, since it uses as much as digits as its factorization.

55138903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15184.

The product of its (nonzero) digits is 16200, while the sum is 34.

The square root of 55138903 is about 7425.5574201537. The cubic root of 55138903 is about 380.6151233099.

The spelling of 55138903 in words is "fifty-five million, one hundred thirty-eight thousand, nine hundred three".