81910536 has 32 divisors (see below), whose sum is σ = 206595360. Its totient is φ = 27060992.

The previous prime is 81910531. The next prime is 81910547. The reversal of 81910536 is 63501918.

It is a junction number, because it is equal to n+sod(n) for n = 81910497 and 81910506.

It is not an unprimeable number, because it can be changed into a prime (81910531) 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, 12390 + ... + 17813.

It is an arithmetic number, because the mean of its divisors is an integer number (6456105).

Almost surely, 2^81910536 is an apocalyptic number.

It is an amenable number.

81910536 is an abundant number, since it is smaller than the sum of its proper divisors (124684824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81910536 is a wasteful number, since it uses less digits than its factorization.

81910536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30325 (or 30321 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 81910536 is about 9050.4439670107. The cubic root of 81910536 is about 434.2900932400.

The spelling of 81910536 in words is "eighty-one million, nine hundred ten thousand, five hundred thirty-six".