68540497920 has 544 divisors, whose sum is σ = 249643069440. Its totient is φ = 17836277760.

The previous prime is 68540497889. The next prime is 68540497931. The reversal of 68540497920 is 2979404586.

68540497920 is a `hidden beast` number, since 6 + 8 + 540 + 4 + 9 + 7 + 92 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nialpdrome in base 4 and base 16.

It is a zygodrome in base 4 and base 16.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 539688897 + ... + 539689023.

Almost surely, 2^68540497920 is an apocalyptic number.

68540497920 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 68540497920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124821534720).

68540497920 is an abundant number, since it is smaller than the sum of its proper divisors (181102571520).

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

68540497920 is an equidigital number, since it uses as much as digits as its factorization.

68540497920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234 (or 198 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 68540497920 in words is "sixty-eight billion, five hundred forty million, four hundred ninety-seven thousand, nine hundred twenty".