81305303766 has 32 divisors (see below), whose sum is σ = 172037986560. Its totient is φ = 25545020256.

The previous prime is 81305303753. The next prime is 81305303797. The reversal of 81305303766 is 66730350318.

It is a super-2 number, since 2×81305303766² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1787706 + ... + 1832621.

It is an arithmetic number, because the mean of its divisors is an integer number (5376187080).

Almost surely, 2^81305303766 is an apocalyptic number.

81305303766 is an abundant number, since it is smaller than the sum of its proper divisors (90732682794).

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

81305303766 is a wasteful number, since it uses less digits than its factorization.

81305303766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3620548.

The product of its (nonzero) digits is 272160, while the sum is 42.

The spelling of 81305303766 in words is "eighty-one billion, three hundred five million, three hundred three thousand, seven hundred sixty-six".