81253336 has 16 divisors (see below), whose sum is σ = 161312040. Its totient is φ = 38236800.

The previous prime is 81253327. The next prime is 81253343. The reversal of 81253336 is 63335218.

It is a super-2 number, since 2×81253336² = 13204209222257792, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81253298 and 81253307.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 298590 + ... + 298861.

Almost surely, 2^81253336 is an apocalyptic number.

It is an amenable number.

81253336 is a deficient number, since it is larger than the sum of its proper divisors (80058704).

81253336 is a wasteful number, since it uses less digits than its factorization.

81253336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597474 (or 597470 counting only the distinct ones).

The product of its digits is 12960, while the sum is 31.

The square root of 81253336 is about 9014.0632347460. The cubic root of 81253336 is about 433.1254803302.

The spelling of 81253336 in words is "eighty-one million, two hundred fifty-three thousand, three hundred thirty-six".