81074025 has 36 divisors (see below), whose sum is σ = 145732860. Its totient is φ = 43084800.

The previous prime is 81074023. The next prime is 81074033. The reversal of 81074025 is 52047018.

It can be written as a sum of positive squares in 6 ways, for example, as 451584 + 80622441 = 672^2 + 8979^2 .

It is not a de Polignac number, because 81074025 - 2¹ = 81074023 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81074025.

It is not an unprimeable number, because it can be changed into a prime (81074023) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 91585 + ... + 92465.

It is an arithmetic number, because the mean of its divisors is an integer number (4048135).

Almost surely, 2^81074025 is an apocalyptic number.

It is an amenable number.

81074025 is a deficient number, since it is larger than the sum of its proper divisors (64658835).

81074025 is a wasteful number, since it uses less digits than its factorization.

81074025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1306 (or 1298 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 81074025 is about 9004.1115608371. Note that the first 3 decimals coincide. The cubic root of 81074025 is about 432.8066365464.

The spelling of 81074025 in words is "eighty-one million, seventy-four thousand, twenty-five".