231340421 has 4 divisors (see below), whose sum is σ = 249135852. Its totient is φ = 213544992.

The previous prime is 231340397. The next prime is 231340429. The reversal of 231340421 is 124043132.

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 141943396 + 89397025 = 11914^2 + 9455^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231340421 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 231340393 and 231340402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231340429) 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, 8897696 + ... + 8897721.

It is an arithmetic number, because the mean of its divisors is an integer number (62283963).

Almost surely, 2^231340421 is an apocalyptic number.

It is an amenable number.

231340421 is a deficient number, since it is larger than the sum of its proper divisors (17795431).

231340421 is a wasteful number, since it uses less digits than its factorization.

231340421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17795430.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 231340421 is about 15209.8790593482. The cubic root of 231340421 is about 613.8805033289.

Adding to 231340421 its reverse (124043132), we get a palindrome (355383553).

The spelling of 231340421 in words is "two hundred thirty-one million, three hundred forty thousand, four hundred twenty-one".