81033340 has 12 divisors (see below), whose sum is σ = 170170056. Its totient is φ = 32413328.

The previous prime is 81033307. The next prime is 81033353. The reversal of 81033340 is 4333018.

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, 2025814 + ... + 2025853.

It is an arithmetic number, because the mean of its divisors is an integer number (14180838).

Almost surely, 2^81033340 is an apocalyptic number.

It is an amenable number.

81033340 is an abundant number, since it is smaller than the sum of its proper divisors (89136716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81033340 is a wasteful number, since it uses less digits than its factorization.

81033340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4051676 (or 4051674 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 81033340 is about 9001.8520316655. The cubic root of 81033340 is about 432.7342266538.

Adding to 81033340 its reverse (4333018), we get a palindrome (85366358).

The spelling of 81033340 in words is "eighty-one million, thirty-three thousand, three hundred forty".