231012989 has 4 divisors (see below), whose sum is σ = 241057056. Its totient is φ = 220968924.

The previous prime is 231012979. The next prime is 231013009. The reversal of 231012989 is 989210132.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 231012989 - 2⁴ = 231012973 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 (231012919) 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, 5021999 + ... + 5022044.

It is an arithmetic number, because the mean of its divisors is an integer number (60264264).

Almost surely, 2^231012989 is an apocalyptic number.

It is an amenable number.

231012989 is a deficient number, since it is larger than the sum of its proper divisors (10044067).

231012989 is a wasteful number, since it uses less digits than its factorization.

231012989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10044066.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 231012989 is about 15199.1114542923. Note that the first 3 decimals coincide. The cubic root of 231012989 is about 613.5907441558.

The spelling of 231012989 in words is "two hundred thirty-one million, twelve thousand, nine hundred eighty-nine".