81774784401 has 16 divisors (see below), whose sum is σ = 112584476160. Its totient is φ = 52741877760.

The previous prime is 81774784397. The next prime is 81774784423. The reversal of 81774784401 is 10448747718.

It is not a de Polignac number, because 81774784401 - 2² = 81774784397 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81774784001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 177531 + ... + 441663.

It is an arithmetic number, because the mean of its divisors is an integer number (7036529760).

Almost surely, 2^81774784401 is an apocalyptic number.

It is an amenable number.

81774784401 is a deficient number, since it is larger than the sum of its proper divisors (30809691759).

81774784401 is a wasteful number, since it uses less digits than its factorization.

81774784401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267496.

The product of its (nonzero) digits is 1404928, while the sum is 51.

The spelling of 81774784401 in words is "eighty-one billion, seven hundred seventy-four million, seven hundred eighty-four thousand, four hundred one".