81751061 has 12 divisors (see below), whose sum is σ = 98167680. Its totient is φ = 67810680.

The previous prime is 81751037. The next prime is 81751063. The reversal of 81751061 is 16015718.

It is a de Polignac number, because none of the positive numbers 2^k-81751061 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 (81751063) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25391 + ... + 28428.

It is an arithmetic number, because the mean of its divisors is an integer number (8180640).

Almost surely, 2^81751061 is an apocalyptic number.

It is an amenable number.

81751061 is a deficient number, since it is larger than the sum of its proper divisors (16416619).

81751061 is a wasteful number, since it uses less digits than its factorization.

81751061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53864 (or 53857 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 29.

The square root of 81751061 is about 9041.6293332563. The cubic root of 81751061 is about 434.0080643663.

Adding to 81751061 its reverse (16015718), we get a palindrome (97766779).

The spelling of 81751061 in words is "eighty-one million, seven hundred fifty-one thousand, sixty-one".