81946655 has 8 divisors (see below), whose sum is σ = 112384032. Its totient is φ = 56191968.

The previous prime is 81946651. The next prime is 81946673. The reversal of 81946655 is 55664918.

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

It is not a de Polignac number, because 81946655 - 2² = 81946651 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81946651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1170632 + ... + 1170701.

It is an arithmetic number, because the mean of its divisors is an integer number (14048004).

Almost surely, 2^81946655 is an apocalyptic number.

81946655 is a deficient number, since it is larger than the sum of its proper divisors (30437377).

81946655 is a wasteful number, since it uses less digits than its factorization.

81946655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2341345.

The product of its digits is 259200, while the sum is 44.

The square root of 81946655 is about 9052.4391740569. The cubic root of 81946655 is about 434.3539182357.

It can be divided in two parts, 819 and 46655, that added together give a palindrome (47474).

The spelling of 81946655 in words is "eighty-one million, nine hundred forty-six thousand, six hundred fifty-five".