81234620 has 24 divisors (see below), whose sum is σ = 178010784. Its totient is φ = 31080896.

The previous prime is 81234617. The next prime is 81234641. The reversal of 81234620 is 2643218.

It is a self number, because there is not a number n which added to its sum of digits gives 81234620.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87839 + ... + 88758.

It is an arithmetic number, because the mean of its divisors is an integer number (7417116).

Almost surely, 2^81234620 is an apocalyptic number.

It is an amenable number.

81234620 is an abundant number, since it is smaller than the sum of its proper divisors (96776164).

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

81234620 is a wasteful number, since it uses less digits than its factorization.

81234620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176629 (or 176627 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 81234620 is about 9013.0250193817. The cubic root of 81234620 is about 433.0922222127.

Adding to 81234620 its reverse (2643218), we get a palindrome (83877838).

The spelling of 81234620 in words is "eighty-one million, two hundred thirty-four thousand, six hundred twenty".