102820644864 has 384 divisors, whose sum is σ = 351606528000. Its totient is φ = 29080829952.

The previous prime is 102820644863. The next prime is 102820644877. The reversal of 102820644864 is 468446028201.

102820644864 is a `hidden beast` number, since 102 + 8 + 2 + 0 + 64 + 486 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is not an unprimeable number, because it can be changed into a prime (102820644863) 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, 39867127 + ... + 39869705.

It is an arithmetic number, because the mean of its divisors is an integer number (915642000).

Almost surely, 2^102820644864 is an apocalyptic number.

102820644864 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 102820644864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175803264000).

102820644864 is an abundant number, since it is smaller than the sum of its proper divisors (248785883136).

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

102820644864 is a wasteful number, since it uses less digits than its factorization.

102820644864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2720 (or 2694 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 45.

The spelling of 102820644864 in words is "one hundred two billion, eight hundred twenty million, six hundred forty-four thousand, eight hundred sixty-four".