231121551 has 16 divisors (see below), whose sum is σ = 319495680. Its totient is φ = 148505280.

The previous prime is 231121459. The next prime is 231121571. The reversal of 231121551 is 155121132.

It is not a de Polignac number, because 231121551 - 2¹¹ = 231119503 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231121571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1111 + ... + 21528.

It is an arithmetic number, because the mean of its divisors is an integer number (19968480).

Almost surely, 2^231121551 is an apocalyptic number.

231121551 is a deficient number, since it is larger than the sum of its proper divisors (88374129).

231121551 is a wasteful number, since it uses less digits than its factorization.

231121551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22766.

The product of its digits is 300, while the sum is 21.

The square root of 231121551 is about 15202.6823620044. The cubic root of 231121551 is about 613.6868458321.

Adding to 231121551 its reverse (155121132), we get a palindrome (386242683).

The spelling of 231121551 in words is "two hundred thirty-one million, one hundred twenty-one thousand, five hundred fifty-one".