81191234 has 8 divisors (see below), whose sum is σ = 124757388. Its totient is φ = 39605440.

The previous prime is 81191207. The next prime is 81191249. The reversal of 81191234 is 43219118.

It can be written as a sum of positive squares in 2 ways, for example, as 50908225 + 30283009 = 7135^2 + 5503^2 .

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 = 81191197 and 81191206.

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, 494987 + ... + 495150.

Almost surely, 2^81191234 is an apocalyptic number.

81191234 is a deficient number, since it is larger than the sum of its proper divisors (43566154).

81191234 is a wasteful number, since it uses less digits than its factorization.

81191234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 990180.

The product of its digits is 1728, while the sum is 29.

The square root of 81191234 is about 9010.6178478504. The cubic root of 81191234 is about 433.0151061370.

The spelling of 81191234 in words is "eighty-one million, one hundred ninety-one thousand, two hundred thirty-four".