81273425 has 12 divisors (see below), whose sum is σ = 100926576. Its totient is φ = 64923600.

The previous prime is 81273419. The next prime is 81273427. The reversal of 81273425 is 52437218.

It is not a de Polignac number, because 81273425 - 2⁸ = 81273169 is a prime.

It is a super-2 number, since 2×81273425² = 13210739222461250, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81273391 and 81273400.

It is not an unprimeable number, because it can be changed into a prime (81273427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18710 + ... + 22640.

It is an arithmetic number, because the mean of its divisors is an integer number (8410548).

Almost surely, 2^81273425 is an apocalyptic number.

It is an amenable number.

81273425 is a deficient number, since it is larger than the sum of its proper divisors (19653151).

81273425 is a wasteful number, since it uses less digits than its factorization.

81273425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4768 (or 4763 counting only the distinct ones).

The product of its digits is 13440, while the sum is 32.

The square root of 81273425 is about 9015.1774802274. The cubic root of 81273425 is about 433.1611725705.

The spelling of 81273425 in words is "eighty-one million, two hundred seventy-three thousand, four hundred twenty-five".