81333670 has 16 divisors (see below), whose sum is σ = 159709968. Its totient is φ = 29575840.

The previous prime is 81333667. The next prime is 81333673. The reversal of 81333670 is 7633318.

It is an interprime number because it is at equal distance from previous prime (81333667) and next prime (81333673).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81333673) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 369589 + ... + 369808.

It is an arithmetic number, because the mean of its divisors is an integer number (9981873).

Almost surely, 2^81333670 is an apocalyptic number.

81333670 is a deficient number, since it is larger than the sum of its proper divisors (78376298).

81333670 is a wasteful number, since it uses less digits than its factorization.

81333670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739415.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 81333670 is about 9018.5181709636. The cubic root of 81333670 is about 433.2681749498.

Adding to 81333670 its reverse (7633318), we get a palindrome (88966988).

The spelling of 81333670 in words is "eighty-one million, three hundred thirty-three thousand, six hundred seventy".