81710530 has 32 divisors (see below), whose sum is σ = 161740800. Its totient is φ = 29473920.

The previous prime is 81710527. The next prime is 81710539. The reversal of 81710530 is 3501718.

It is a super-2 number, since 2×81710530² = 13353221425761800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81710495 and 81710504.

It is not an unprimeable number, because it can be changed into a prime (81710539) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11046 + ... + 16894.

It is an arithmetic number, because the mean of its divisors is an integer number (5054400).

Almost surely, 2^81710530 is an apocalyptic number.

81710530 is a deficient number, since it is larger than the sum of its proper divisors (80030270).

81710530 is a wasteful number, since it uses less digits than its factorization.

81710530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5994.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 81710530 is about 9039.3877005027. The cubic root of 81710530 is about 433.9363275247.

The spelling of 81710530 in words is "eighty-one million, seven hundred ten thousand, five hundred thirty".