81169534 has 4 divisors (see below), whose sum is σ = 121754304. Its totient is φ = 40584766.

The previous prime is 81169489. The next prime is 81169537. The reversal of 81169534 is 43596118.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 81169493 and 81169502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81169537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20292382 + ... + 20292385.

It is an arithmetic number, because the mean of its divisors is an integer number (30438576).

Almost surely, 2^81169534 is an apocalyptic number.

81169534 is a deficient number, since it is larger than the sum of its proper divisors (40584770).

81169534 is a wasteful number, since it uses less digits than its factorization.

81169534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40584769.

The product of its digits is 25920, while the sum is 37.

The square root of 81169534 is about 9009.4136324180. The cubic root of 81169534 is about 432.9765253503.

The spelling of 81169534 in words is "eighty-one million, one hundred sixty-nine thousand, five hundred thirty-four".