81929496626 has 4 divisors (see below), whose sum is σ = 122894244942. Its totient is φ = 40964748312.

The previous prime is 81929496581. The next prime is 81929496629. The reversal of 81929496626 is 62669492918.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 62669492918 = 2 ⋅31334746459.

It can be written as a sum of positive squares in only one way, i.e., 80229996001 + 1699500625 = 283249^2 + 41225^2 .

It is not an unprimeable number, because it can be changed into a prime (81929496629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20482374155 + ... + 20482374158.

Almost surely, 2^81929496626 is an apocalyptic number.

81929496626 is a deficient number, since it is larger than the sum of its proper divisors (40964748316).

81929496626 is a wasteful number, since it uses less digits than its factorization.

81929496626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40964748315.

The product of its digits is 20155392, while the sum is 62.

The spelling of 81929496626 in words is "eighty-one billion, nine hundred twenty-nine million, four hundred ninety-six thousand, six hundred twenty-six".