68406246640 has 40 divisors (see below), whose sum is σ = 162923665968. Its totient is φ = 26695119360.

The previous prime is 68406246607. The next prime is 68406246677. The reversal of 68406246640 is 4664260486.

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

It is a super-2 number, since 2×68406246640² (a number of 22 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

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, 10424502 + ... + 10431061.

Almost surely, 2^68406246640 is an apocalyptic number.

It is an amenable number.

68406246640 is an abundant number, since it is smaller than the sum of its proper divisors (94517419328).

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

68406246640 is a wasteful number, since it uses less digits than its factorization.

68406246640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20855617 (or 20855611 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 46.

The spelling of 68406246640 in words is "sixty-eight billion, four hundred six million, two hundred forty-six thousand, six hundred forty".