81821182628 has 24 divisors (see below), whose sum is σ = 148065899520. Its totient is φ = 39521280960.

The previous prime is 81821182621. The next prime is 81821182657. The reversal of 81821182628 is 82628112818.

It is not an unprimeable number, because it can be changed into a prime (81821182621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 509276 + ... + 650387.

It is an arithmetic number, because the mean of its divisors is an integer number (6169412480).

Almost surely, 2^81821182628 is an apocalyptic number.

It is an amenable number.

81821182628 is a deficient number, since it is larger than the sum of its proper divisors (66244716892).

81821182628 is a wasteful number, since it uses less digits than its factorization.

81821182628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1160267 (or 1160265 counting only the distinct ones).

The product of its digits is 196608, while the sum is 47.

The spelling of 81821182628 in words is "eighty-one billion, eight hundred twenty-one million, one hundred eighty-two thousand, six hundred twenty-eight".