81126309 has 8 divisors (see below), whose sum is σ = 118001952. Its totient is φ = 49167440.

The previous prime is 81126307. The next prime is 81126341. The reversal of 81126309 is 90362118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81126309 - 2¹ = 81126307 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81126301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1229154 + ... + 1229219.

It is an arithmetic number, because the mean of its divisors is an integer number (14750244).

Almost surely, 2^81126309 is an apocalyptic number.

It is an amenable number.

81126309 is a deficient number, since it is larger than the sum of its proper divisors (36875643).

81126309 is a wasteful number, since it uses less digits than its factorization.

81126309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2458387.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 81126309 is about 9007.0144332070. The cubic root of 81126309 is about 432.8996544172.

The spelling of 81126309 in words is "eighty-one million, one hundred twenty-six thousand, three hundred nine".