68217840 has 60 divisors (see below), whose sum is σ = 229100664. Its totient is φ = 18191232.

The previous prime is 68217833. The next prime is 68217841. The reversal of 68217840 is 4871286.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 68217795 and 68217804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68217841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 46654 + ... + 48093.

Almost surely, 2^68217840 is an apocalyptic number.

68217840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

68217840 is an abundant number, since it is smaller than the sum of its proper divisors (160882824).

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

68217840 is a wasteful number, since it uses less digits than its factorization.

68217840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94766 (or 94757 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 68217840 is about 8259.4091798385. The cubic root of 68217840 is about 408.6009023306.

The spelling of 68217840 in words is "sixty-eight million, two hundred seventeen thousand, eight hundred forty".