102644640 has 288 divisors, whose sum is σ = 424569600. Its totient is φ = 22044672.

The previous prime is 102644611. The next prime is 102644651. The reversal of 102644640 is 46446201.

102644640 is a `hidden beast` number, since 10 + 2 + 6 + 4 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 171061 + ... + 171659.

It is an arithmetic number, because the mean of its divisors is an integer number (1474200).

Almost surely, 2^102644640 is an apocalyptic number.

102644640 is a gapful number since it is divisible by the number (10) 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 102644640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212284800).

102644640 is an abundant number, since it is smaller than the sum of its proper divisors (321924960).

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

102644640 is a wasteful number, since it uses less digits than its factorization.

102644640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644 (or 633 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 102644640 is about 10131.3691078748. The cubic root of 102644640 is about 468.2151104042.

The spelling of 102644640 in words is "one hundred two million, six hundred forty-four thousand, six hundred forty".