81110400770 has 64 divisors (see below), whose sum is σ = 171341153280. Its totient is φ = 27066287808.

The previous prime is 81110400739. The next prime is 81110400779. The reversal of 81110400770 is 7700401118.

It is a super-2 number, since 2×81110400770² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81110400779) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 804221 + ... + 899439.

It is an arithmetic number, because the mean of its divisors is an integer number (2677205520).

Almost surely, 2^81110400770 is an apocalyptic number.

81110400770 is an abundant number, since it is smaller than the sum of its proper divisors (90230752510).

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

81110400770 is a wasteful number, since it uses less digits than its factorization.

81110400770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95559.

The product of its (nonzero) digits is 1568, while the sum is 29.

Adding to 81110400770 its reverse (7700401118), we get a palindrome (88810801888).

The spelling of 81110400770 in words is "eighty-one billion, one hundred ten million, four hundred thousand, seven hundred seventy".