87729309 has 6 divisors (see below), whose sum is σ = 126720126. Its totient is φ = 58486200.

The previous prime is 87729293. The next prime is 87729359. The reversal of 87729309 is 90392778.

It can be written as a sum of positive squares in only one way, i.e., 60793209 + 26936100 = 7797^2 + 5190^2 .

It is not a de Polignac number, because 87729309 - 2⁴ = 87729293 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87729359) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4873842 + ... + 4873859.

It is an arithmetic number, because the mean of its divisors is an integer number (21120021).

Almost surely, 2^87729309 is an apocalyptic number.

It is an amenable number.

87729309 is a deficient number, since it is larger than the sum of its proper divisors (38990817).

87729309 is a wasteful number, since it uses less digits than its factorization.

87729309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9747707 (or 9747704 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The square root of 87729309 is about 9366.3925286099. The cubic root of 87729309 is about 444.3394804465.

It can be divided in two parts, 8772 and 9309, that added together give a palindrome (18081).

The spelling of 87729309 in words is "eighty-seven million, seven hundred twenty-nine thousand, three hundred nine".