81771801 has 8 divisors (see below), whose sum is σ = 114767520. Its totient is φ = 51645312.

The previous prime is 81771791. The next prime is 81771821. The reversal of 81771801 is 10817718.

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

It is not a de Polignac number, because 81771801 - 2¹³ = 81763609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81771821) 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 7 ways as a sum of consecutive naturals, for example, 717240 + ... + 717353.

It is an arithmetic number, because the mean of its divisors is an integer number (14345940).

Almost surely, 2^81771801 is an apocalyptic number.

It is an amenable number.

81771801 is a deficient number, since it is larger than the sum of its proper divisors (32995719).

81771801 is a wasteful number, since it uses less digits than its factorization.

81771801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1434615.

The product of its (nonzero) digits is 3136, while the sum is 33.

The square root of 81771801 is about 9042.7761777012. The cubic root of 81771801 is about 434.0447634462.

The spelling of 81771801 in words is "eighty-one million, seven hundred seventy-one thousand, eight hundred one".