81751192 has 8 divisors (see below), whose sum is σ = 153283500. Its totient is φ = 40875592.

The previous prime is 81751169. The next prime is 81751193. The reversal of 81751192 is 29115718.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81751193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5109442 + ... + 5109457.

Almost surely, 2^81751192 is an apocalyptic number.

It is an amenable number.

81751192 is a deficient number, since it is larger than the sum of its proper divisors (71532308).

81751192 is a wasteful number, since it uses less digits than its factorization.

81751192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10218905 (or 10218901 counting only the distinct ones).

The product of its digits is 5040, while the sum is 34.

The square root of 81751192 is about 9041.6365775229. The cubic root of 81751192 is about 434.0082961880.

The spelling of 81751192 in words is "eighty-one million, seven hundred fifty-one thousand, one hundred ninety-two".