231399381 has 8 divisors (see below), whose sum is σ = 319171680. Its totient is φ = 148946672.

The previous prime is 231399361. The next prime is 231399391. The reversal of 231399381 is 183993132.

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 231399381 - 2¹⁰ = 231398357 is a prime.

It is a super-2 number, since 2×231399381² = 107091347054366322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231399331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1329795 + ... + 1329968.

It is an arithmetic number, because the mean of its divisors is an integer number (39896460).

Almost surely, 2^231399381 is an apocalyptic number.

It is an amenable number.

231399381 is a deficient number, since it is larger than the sum of its proper divisors (87772299).

231399381 is a wasteful number, since it uses less digits than its factorization.

231399381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2659795.

The product of its digits is 34992, while the sum is 39.

The square root of 231399381 is about 15211.8171498345. The cubic root of 231399381 is about 613.9326506073.

The spelling of 231399381 in words is "two hundred thirty-one million, three hundred ninety-nine thousand, three hundred eighty-one".