68421501605 has 4 divisors (see below), whose sum is σ = 82105801932. Its totient is φ = 54737201280.

The previous prime is 68421501497. The next prime is 68421501607. The reversal of 68421501605 is 50610512486.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14603997409 + 53817504196 = 120847^2 + 231986^2 .

It is not a de Polignac number, because 68421501605 - 2¹⁴ = 68421485221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68421501607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6842150156 + ... + 6842150165.

It is an arithmetic number, because the mean of its divisors is an integer number (20526450483).

Almost surely, 2^68421501605 is an apocalyptic number.

It is an amenable number.

68421501605 is a deficient number, since it is larger than the sum of its proper divisors (13684300327).

68421501605 is a wasteful number, since it uses less digits than its factorization.

68421501605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13684300326.

The product of its (nonzero) digits is 57600, while the sum is 38.

The spelling of 68421501605 in words is "sixty-eight billion, four hundred twenty-one million, five hundred one thousand, six hundred five".