102805840 has 40 divisors (see below), whose sum is σ = 239672160. Its totient is φ = 41010816.

The previous prime is 102805793. The next prime is 102805897. The reversal of 102805840 is 48508201.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×102805840³ (a number of 25 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 102805799 and 102805808.

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, 31987 + ... + 35053.

It is an arithmetic number, because the mean of its divisors is an integer number (5991804).

Almost surely, 2^102805840 is an apocalyptic number.

102805840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

102805840 is an abundant number, since it is smaller than the sum of its proper divisors (136866320).

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

102805840 is a wasteful number, since it uses less digits than its factorization.

102805840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3499 (or 3493 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 102805840 is about 10139.3214763119. The cubic root of 102805840 is about 468.4600876358.

The spelling of 102805840 in words is "one hundred two million, eight hundred five thousand, eight hundred forty".