81653230 has 8 divisors (see below), whose sum is σ = 146975832. Its totient is φ = 32661288.

The previous prime is 81653213. The next prime is 81653237. The reversal of 81653230 is 3235618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81653237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4082652 + ... + 4082671.

It is an arithmetic number, because the mean of its divisors is an integer number (18371979).

Almost surely, 2^81653230 is an apocalyptic number.

81653230 is a deficient number, since it is larger than the sum of its proper divisors (65322602).

81653230 is a wasteful number, since it uses less digits than its factorization.

81653230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8165330.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 81653230 is about 9036.2176821942. The cubic root of 81653230 is about 433.8348703197.

Adding to 81653230 its reverse (3235618), we get a palindrome (84888848).

The spelling of 81653230 in words is "eighty-one million, six hundred fifty-three thousand, two hundred thirty".