68640064 has 28 divisors (see below), whose sum is σ = 136938004. Its totient is φ = 34136064.

The previous prime is 68640059. The next prime is 68640133. The reversal of 68640064 is 46004686.

It can be written as a sum of positive squares in 2 ways, for example, as 43560000 + 25080064 = 6600^2 + 5008^2 .

It is a super-2 number, since 2×68640064² = 9422916771848192, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9574 + ... + 15130.

It is an arithmetic number, because the mean of its divisors is an integer number (4890643).

Almost surely, 2^68640064 is an apocalyptic number.

68640064 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

68640064 is a deficient number, since it is larger than the sum of its proper divisors (68297940).

68640064 is a wasteful number, since it uses less digits than its factorization.

68640064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5762 (or 5752 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 68640064 is about 8284.9299333187. The cubic root of 68640064 is about 409.4421602535.

The spelling of 68640064 in words is "sixty-eight million, six hundred forty thousand, sixty-four".