231638149 has 4 divisors (see below), whose sum is σ = 231682860. Its totient is φ = 231593440.

The previous prime is 231638131. The next prime is 231638153. The reversal of 231638149 is 941836132.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7387524 + 224250625 = 2718^2 + 14975^2 .

It is a cyclic number.

It is not a de Polignac number, because 231638149 - 2²³ = 223249541 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 (231638749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13384 + ... + 25345.

It is an arithmetic number, because the mean of its divisors is an integer number (57920715).

Almost surely, 2^231638149 is an apocalyptic number.

It is an amenable number.

231638149 is a deficient number, since it is larger than the sum of its proper divisors (44711).

231638149 is an equidigital number, since it uses as much as digits as its factorization.

231638149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44710.

The product of its digits is 31104, while the sum is 37.

The square root of 231638149 is about 15219.6632354333. The cubic root of 231638149 is about 614.1437388723.

The spelling of 231638149 in words is "two hundred thirty-one million, six hundred thirty-eight thousand, one hundred forty-nine".