81353280826 has 4 divisors (see below), whose sum is σ = 122029921242. Its totient is φ = 40676640412.

The previous prime is 81353280797. The next prime is 81353280851. The reversal of 81353280826 is 62808235318.

It is a happy number.

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., 41891855625 + 39461425201 = 204675^2 + 198649^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20338320205 + ... + 20338320208.

Almost surely, 2^81353280826 is an apocalyptic number.

81353280826 is a deficient number, since it is larger than the sum of its proper divisors (40676640416).

81353280826 is a wasteful number, since it uses less digits than its factorization.

81353280826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40676640415.

The product of its (nonzero) digits is 552960, while the sum is 46.

The spelling of 81353280826 in words is "eighty-one billion, three hundred fifty-three million, two hundred eighty thousand, eight hundred twenty-six".