81191434 has 8 divisors (see below), whose sum is σ = 123851520. Its totient is φ = 39907596.

The previous prime is 81191423. The next prime is 81191443. The reversal of 81191434 is 43419118.

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

It is a junction number, because it is equal to n+sod(n) for n = 81191396 and 81191405.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 343914 + ... + 344149.

It is an arithmetic number, because the mean of its divisors is an integer number (15481440).

Almost surely, 2^81191434 is an apocalyptic number.

81191434 is a deficient number, since it is larger than the sum of its proper divisors (42660086).

81191434 is a wasteful number, since it uses less digits than its factorization.

81191434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688124.

The product of its digits is 3456, while the sum is 31.

The square root of 81191434 is about 9010.6289458617. The cubic root of 81191434 is about 433.0154616883.

The spelling of 81191434 in words is "eighty-one million, one hundred ninety-one thousand, four hundred thirty-four".