81464166250 has 20 divisors (see below), whose sum is σ = 152696435562. Its totient is φ = 32585666000.

The previous prime is 81464166239. The next prime is 81464166271. The reversal of 81464166250 is 5266146418.

It can be written as a sum of positive squares in 5 ways, for example, as 1823375401 + 79640790849 = 42701^2 + 282207^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81464166197 and 81464166206.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 32584417 + ... + 32586916.

Almost surely, 2^81464166250 is an apocalyptic number.

81464166250 is a deficient number, since it is larger than the sum of its proper divisors (71232269312).

81464166250 is an equidigital number, since it uses as much as digits as its factorization.

81464166250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65171355 (or 65171340 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 43.

The spelling of 81464166250 in words is "eighty-one billion, four hundred sixty-four million, one hundred sixty-six thousand, two hundred fifty".