81717061 has 8 divisors (see below), whose sum is σ = 82353024. Its totient is φ = 81084000.

The previous prime is 81717037. The next prime is 81717133. The reversal of 81717061 is 16071718.

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

It is not a de Polignac number, because 81717061 - 2¹¹ = 81715013 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 (81717001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108436 + ... + 109186.

It is an arithmetic number, because the mean of its divisors is an integer number (10294128).

Almost surely, 2^81717061 is an apocalyptic number.

It is an amenable number.

81717061 is a deficient number, since it is larger than the sum of its proper divisors (635963).

81717061 is a wasteful number, since it uses less digits than its factorization.

81717061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1451.

The product of its (nonzero) digits is 2352, while the sum is 31.

The square root of 81717061 is about 9039.7489456290. The cubic root of 81717061 is about 433.9478885097.

Adding to 81717061 its reverse (16071718), we get a palindrome (97788779).

The spelling of 81717061 in words is "eighty-one million, seven hundred seventeen thousand, sixty-one".