68521654731816 has 192 divisors, whose sum is σ = 218064140461440. Its totient is φ = 19163318976000.

The previous prime is 68521654731781. The next prime is 68521654731841. The reversal of 68521654731816 is 61813745612586.

It is a happy number.

68521654731816 is a `hidden beast` number, since 6 + 8 + 5 + 2 + 1 + 6 + 547 + 3 + 1 + 81 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 54784381 + ... + 56021171.

It is an arithmetic number, because the mean of its divisors is an integer number (1135750731570).

Almost surely, 2^{68521654731816} is an apocalyptic number.

68521654731816 is a gapful number since it is divisible by the number (66) 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 68521654731816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109032070230720).

68521654731816 is an abundant number, since it is smaller than the sum of its proper divisors (149542485729624).

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

68521654731816 is a wasteful number, since it uses less digits than its factorization.

68521654731816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242208 (or 1242201 counting only the distinct ones).

The product of its digits is 58060800, while the sum is 63.

The spelling of 68521654731816 in words is "sixty-eight trillion, five hundred twenty-one billion, six hundred fifty-four million, seven hundred thirty-one thousand, eight hundred sixteen".