81026761104 has 75 divisors (see below), whose sum is σ = 234544617307. Its totient is φ = 27005504544.

The previous prime is 81026761021. The next prime is 81026761177. The reversal of 81026761104 is 40116762018.

It is a happy number.

The square root of 81026761104 is 284652.

It is a perfect power (a square), and thus also a powerful number.

81026761104 is a `hidden beast` number, since 8 + 10 + 26 + 7 + 611 + 0 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 10243519 + ... + 10251425.

Almost surely, 2^81026761104 is an apocalyptic number.

81026761104 is the 284652-nd square number.

It is an amenable number.

81026761104 is an abundant number, since it is smaller than the sum of its proper divisors (153517856203).

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

81026761104 is an frugal number, since it uses more digits than its factorization.

81026761104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15834 (or 7912 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

Multiplying 81026761104 by its sum of digits (36), we get a square (2916963399744 = 1707912²).

81026761104 divided by its sum of digits (36) gives a square (2250743364 = 47442²).

The spelling of 81026761104 in words is "eighty-one billion, twenty-six million, seven hundred sixty-one thousand, one hundred four".