68655840 has 96 divisors (see below), whose sum is σ = 235944576. Its totient is φ = 16642560.

The previous prime is 68655827. The next prime is 68655841. The reversal of 68655840 is 4855686.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×68655840² = 9427248732211200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 68655792 and 68655801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68655841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1222 + ... + 11781.

It is an arithmetic number, because the mean of its divisors is an integer number (2457756).

Almost surely, 2^68655840 is an apocalyptic number.

68655840 is a gapful number since it is divisible by the number (60) 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 68655840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117972288).

68655840 is an abundant number, since it is smaller than the sum of its proper divisors (167288736).

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

68655840 is a wasteful number, since it uses less digits than its factorization.

68655840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13032 (or 13024 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 42.

The square root of 68655840 is about 8285.8819687466. The cubic root of 68655840 is about 409.4735261174.

The spelling of 68655840 in words is "sixty-eight million, six hundred fifty-five thousand, eight hundred forty".