81136210 has 16 divisors (see below), whose sum is σ = 148521600. Its totient is φ = 31904176.

The previous prime is 81136201. The next prime is 81136217. The reversal of 81136210 is 1263118.

It is not an unprimeable number, because it can be changed into a prime (81136217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68170 + ... + 69349.

It is an arithmetic number, because the mean of its divisors is an integer number (9282600).

Almost surely, 2^81136210 is an apocalyptic number.

81136210 is a deficient number, since it is larger than the sum of its proper divisors (67385390).

81136210 is a wasteful number, since it uses less digits than its factorization.

81136210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137585.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 81136210 is about 9007.5640436247. The cubic root of 81136210 is about 432.9172646728.

Adding to 81136210 its reverse (1263118), we get a palindrome (82399328).

The spelling of 81136210 in words is "eighty-one million, one hundred thirty-six thousand, two hundred ten".