231739729 has 9 divisors (see below), whose sum is σ = 251151579. Its totient is φ = 213730920.

The previous prime is 231739723. The next prime is 231739757. The reversal of 231739729 is 927937132.

The square root of 231739729 is 15223.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 34281025 + 197458704 = 5855^2 + 14052^2 .

It is not a de Polignac number, because 231739729 - 2¹³ = 231731537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231739723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 197314 + ... + 198484.

It is an arithmetic number, because the mean of its divisors is an integer number (27905731).

Almost surely, 2^231739729 is an apocalyptic number.

231739729 is the 15223-rd square number.

231739729 is the 7612-nd centered octagonal number.

It is an amenable number.

231739729 is a deficient number, since it is larger than the sum of its proper divisors (19411850).

231739729 is an frugal number, since it uses more digits than its factorization.

231739729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2368 (or 1184 counting only the distinct ones).

The product of its digits is 142884, while the sum is 43.

The cubic root of 231739729 is about 614.2334989922.

Multiplying 231739729 by its product of digits (142884), we get a square (33111899438436 = 5754294²).

The spelling of 231739729 in words is "two hundred thirty-one million, seven hundred thirty-nine thousand, seven hundred twenty-nine".