81738354226 has 4 divisors (see below), whose sum is σ = 122607531342. Its totient is φ = 40869177112.

The previous prime is 81738354223. The next prime is 81738354239. The reversal of 81738354226 is 62245383718.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 67967097025 + 13771257201 = 260705^2 + 117351^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 81738354226.

It is not an unprimeable number, because it can be changed into a prime (81738354221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20434588555 + ... + 20434588558.

Almost surely, 2^81738354226 is an apocalyptic number.

81738354226 is a deficient number, since it is larger than the sum of its proper divisors (40869177116).

81738354226 is a wasteful number, since it uses less digits than its factorization.

81738354226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40869177115.

The product of its digits is 1935360, while the sum is 49.

The spelling of 81738354226 in words is "eighty-one billion, seven hundred thirty-eight million, three hundred fifty-four thousand, two hundred twenty-six".