81761193 has 12 divisors (see below), whose sum is σ = 118279408. Its totient is φ = 54424440.

The previous prime is 81761191. The next prime is 81761213. The reversal of 81761193 is 39116718.

It is not a de Polignac number, because 81761193 - 2¹ = 81761191 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81761191) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 355 + ... + 12792.

Almost surely, 2^81761193 is an apocalyptic number.

It is an amenable number.

81761193 is a deficient number, since it is larger than the sum of its proper divisors (36518215).

81761193 is a wasteful number, since it uses less digits than its factorization.

81761193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13844 (or 13841 counting only the distinct ones).

The product of its digits is 9072, while the sum is 36.

The square root of 81761193 is about 9042.1896131413. The cubic root of 81761193 is about 434.0259935446.

The spelling of 81761193 in words is "eighty-one million, seven hundred sixty-one thousand, one hundred ninety-three".