81783455 has 8 divisors (see below), whose sum is σ = 105689472. Its totient is φ = 60393888.

The previous prime is 81783421. The next prime is 81783461. The reversal of 81783455 is 55438718.

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

It is a cyclic number.

It is not a de Polignac number, because 81783455 - 2⁸ = 81783199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 629039 + ... + 629168.

It is an arithmetic number, because the mean of its divisors is an integer number (13211184).

Almost surely, 2^81783455 is an apocalyptic number.

81783455 is a deficient number, since it is larger than the sum of its proper divisors (23906017).

81783455 is a wasteful number, since it uses less digits than its factorization.

81783455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1258225.

The product of its digits is 134400, while the sum is 41.

The square root of 81783455 is about 9043.4205365006. The cubic root of 81783455 is about 434.0653822794.

The spelling of 81783455 in words is "eighty-one million, seven hundred eighty-three thousand, four hundred fifty-five".