81644001248 has 48 divisors (see below), whose sum is σ = 164552227056. Its totient is φ = 39864038400.

The previous prime is 81644001227. The next prime is 81644001259. The reversal of 81644001248 is 84210044618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62915 + ... + 408957.

It is an arithmetic number, because the mean of its divisors is an integer number (3428171397).

Almost surely, 2^81644001248 is an apocalyptic number.

It is an amenable number.

81644001248 is an abundant number, since it is smaller than the sum of its proper divisors (82908225808).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81644001248 is a wasteful number, since it uses less digits than its factorization.

81644001248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346227 (or 346219 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 38.

The spelling of 81644001248 in words is "eighty-one billion, six hundred forty-four million, one thousand, two hundred forty-eight".