231206389 has 2 divisors, whose sum is σ = 231206390. Its totient is φ = 231206388.

The previous prime is 231206351. The next prime is 231206407. The reversal of 231206389 is 983602132.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 222308100 + 8898289 = 14910^2 + 2983^2 .

It is a cyclic number.

It is not a de Polignac number, because 231206389 - 2¹¹ = 231204341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231206329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115603194 + 115603195.

It is an arithmetic number, because the mean of its divisors is an integer number (115603195).

Almost surely, 2^231206389 is an apocalyptic number.

It is an amenable number.

231206389 is a deficient number, since it is larger than the sum of its proper divisors (1).

231206389 is an equidigital number, since it uses as much as digits as its factorization.

231206389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 231206389 is about 15205.4723372870. The cubic root of 231206389 is about 613.7619255111.

The spelling of 231206389 in words is "two hundred thirty-one million, two hundred six thousand, three hundred eighty-nine".