81341892025 has 9 divisors (see below), whose sum is σ = 100865714413. Its totient is φ = 65072372800.

The previous prime is 81341892019. The next prime is 81341892059. The reversal of 81341892025 is 52029814318.

The square root of 81341892025 is 285205.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 5278458409 + 76063433616 = 72653^2 + 275796^2 .

It is not a de Polignac number, because 81341892025 - 2³⁵ = 46982153657 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1397505 + ... + 1454545.

Almost surely, 2^81341892025 is an apocalyptic number.

81341892025 is the 285205-th square number.

81341892025 is the 142603-rd centered octagonal number.

It is an amenable number.

81341892025 is a deficient number, since it is larger than the sum of its proper divisors (19523822388).

81341892025 is an frugal number, since it uses more digits than its factorization.

81341892025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114092 (or 57046 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 43.

The spelling of 81341892025 in words is "eighty-one billion, three hundred forty-one million, eight hundred ninety-two thousand, twenty-five".