81775220756210 has 16 divisors (see below), whose sum is σ = 152271100719000. Its totient is φ = 31582154222976.

The previous prime is 81775220756171. The next prime is 81775220756263. The reversal of 81775220756210 is 1265702257718.

It can be written as a sum of positive squares in 4 ways, for example, as 62626378624489 + 19148842131721 = 7913683^2 + 4375939^2 .

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, 140991759635 + ... + 140991760214.

Almost surely, 2^{81775220756210} is an apocalyptic number.

81775220756210 is a deficient number, since it is larger than the sum of its proper divisors (70495879962790).

81775220756210 is a wasteful number, since it uses less digits than its factorization.

81775220756210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281983519885.

The product of its (nonzero) digits is 3292800, while the sum is 53.

The spelling of 81775220756210 in words is "eighty-one trillion, seven hundred seventy-five billion, two hundred twenty million, seven hundred fifty-six thousand, two hundred ten".