81290425 has 12 divisors (see below), whose sum is σ = 103145680. Its totient is φ = 63519120.

The previous prime is 81290411. The next prime is 81290437. The reversal of 81290425 is 52409218.

It is not a de Polignac number, because 81290425 - 2⁹ = 81289913 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36735 + ... + 38884.

Almost surely, 2^81290425 is an apocalyptic number.

It is an amenable number.

81290425 is a deficient number, since it is larger than the sum of its proper divisors (21855255).

81290425 is a wasteful number, since it uses less digits than its factorization.

81290425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75672 (or 75667 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 81290425 is about 9016.1202853556. The cubic root of 81290425 is about 433.1913719728.

The spelling of 81290425 in words is "eighty-one million, two hundred ninety thousand, four hundred twenty-five".