81208790 has 16 divisors (see below), whose sum is σ = 157420368. Its totient is φ = 29984736.

The previous prime is 81208781. The next prime is 81208817. The reversal of 81208790 is 9780218.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81208790.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 312212 + ... + 312471.

It is an arithmetic number, because the mean of its divisors is an integer number (9838773).

Almost surely, 2^81208790 is an apocalyptic number.

81208790 is a deficient number, since it is larger than the sum of its proper divisors (76211578).

81208790 is a wasteful number, since it uses less digits than its factorization.

81208790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624703.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 81208790 is about 9011.5919792232. The cubic root of 81208790 is about 433.0463142078.

The spelling of 81208790 in words is "eighty-one million, two hundred eight thousand, seven hundred ninety".