81746141 has 4 divisors (see below), whose sum is σ = 82050300. Its totient is φ = 81441984.

The previous prime is 81746123. The next prime is 81746143. The reversal of 81746141 is 14164718.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24304900 + 57441241 = 4930^2 + 7579^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81746141 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81746098 and 81746107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81746143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151676 + ... + 152213.

It is an arithmetic number, because the mean of its divisors is an integer number (20512575).

Almost surely, 2^81746141 is an apocalyptic number.

It is an amenable number.

81746141 is a deficient number, since it is larger than the sum of its proper divisors (304159).

81746141 is a wasteful number, since it uses less digits than its factorization.

81746141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304158.

The product of its digits is 5376, while the sum is 32.

The square root of 81746141 is about 9041.3572543065. The cubic root of 81746141 is about 433.9993575985. Note that the first 3 decimals are identical.

The spelling of 81746141 in words is "eighty-one million, seven hundred forty-six thousand, one hundred forty-one".