81203910 has 64 divisors (see below), whose sum is σ = 207187200. Its totient is φ = 20310912.

The previous prime is 81203851. The next prime is 81203953. The reversal of 81203910 is 1930218.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 61477 + ... + 62783.

It is an arithmetic number, because the mean of its divisors is an integer number (3237300).

Almost surely, 2^81203910 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81203910, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103593600).

81203910 is an abundant number, since it is smaller than the sum of its proper divisors (125983290).

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

81203910 is a wasteful number, since it uses less digits than its factorization.

81203910 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1445.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 81203910 is about 9011.3212127856. The cubic root of 81203910 is about 433.0376398252.

The spelling of 81203910 in words is "eighty-one million, two hundred three thousand, nine hundred ten".