81512206 has 16 divisors (see below), whose sum is σ = 126443520. Its totient is φ = 39369240.

The previous prime is 81512201. The next prime is 81512231. The reversal of 81512206 is 60221518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81512201) 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, 51235 + ... + 52801.

It is an arithmetic number, because the mean of its divisors is an integer number (7902720).

Almost surely, 2^81512206 is an apocalyptic number.

81512206 is a deficient number, since it is larger than the sum of its proper divisors (44931314).

81512206 is a wasteful number, since it uses less digits than its factorization.

81512206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2439.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 81512206 is about 9028.4110451397. The cubic root of 81512206 is about 433.5849664080.

It can be divided in two parts, 81512 and 206, that added together give a palindrome (81718).

The spelling of 81512206 in words is "eighty-one million, five hundred twelve thousand, two hundred six".