81309134 has 8 divisors (see below), whose sum is σ = 122133648. Its totient is φ = 40597920.

The previous prime is 81309131. The next prime is 81309161. The reversal of 81309134 is 43190318.

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

It is a super-2 number, since 2×81309134² = 13222350543659912, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81309097 and 81309106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81309131) 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, 26507 + ... + 29414.

It is an arithmetic number, because the mean of its divisors is an integer number (15266706).

Almost surely, 2^81309134 is an apocalyptic number.

81309134 is a deficient number, since it is larger than the sum of its proper divisors (40824514).

81309134 is a wasteful number, since it uses less digits than its factorization.

81309134 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56650.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 81309134 is about 9017.1577561890. The cubic root of 81309134 is about 433.2246024371.

The spelling of 81309134 in words is "eighty-one million, three hundred nine thousand, one hundred thirty-four".