81573253006 has 64 divisors (see below), whose sum is σ = 143100148608. Its totient is φ = 34155675648.

The previous prime is 81573253001. The next prime is 81573253019. The reversal of 81573253006 is 60035237518.

It is a self number, because there is not a number n which added to its sum of digits gives 81573253006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81573253001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 54636396 + ... + 54637888.

It is an arithmetic number, because the mean of its divisors is an integer number (2235939822).

Almost surely, 2^81573253006 is an apocalyptic number.

81573253006 is a deficient number, since it is larger than the sum of its proper divisors (61526895602).

81573253006 is a wasteful number, since it uses less digits than its factorization.

81573253006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2045.

The product of its (nonzero) digits is 151200, while the sum is 40.

The spelling of 81573253006 in words is "eighty-one billion, five hundred seventy-three million, two hundred fifty-three thousand, six".