81852425 has 6 divisors (see below), whose sum is σ = 101497038. Its totient is φ = 65481920.

The previous prime is 81852409. The next prime is 81852443. The reversal of 81852425 is 52425818.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 1373584 + 80478841 = 1172^2 + 8971^2 .

It is not a de Polignac number, because 81852425 - 2⁴ = 81852409 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 (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1637024 + ... + 1637073.

It is an arithmetic number, because the mean of its divisors is an integer number (16916173).

Almost surely, 2^81852425 is an apocalyptic number.

It is an amenable number.

81852425 is a deficient number, since it is larger than the sum of its proper divisors (19644613).

81852425 is a wasteful number, since it uses less digits than its factorization.

81852425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3274107 (or 3274102 counting only the distinct ones).

The product of its digits is 25600, while the sum is 35.

The square root of 81852425 is about 9047.2330024157. The cubic root of 81852425 is about 434.1873673341.

The spelling of 81852425 in words is "eighty-one million, eight hundred fifty-two thousand, four hundred twenty-five".