68075521 has 4 divisors (see below), whose sum is σ = 68895792. Its totient is φ = 67255252.

The previous prime is 68075507. The next prime is 68075533. The reversal of 68075521 is 12557086.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12557086 = 2 ⋅6278543.

It is a cyclic number.

It is not a de Polignac number, because 68075521 - 2⁷ = 68075393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68075221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 410011 + ... + 410176.

It is an arithmetic number, because the mean of its divisors is an integer number (17223948).

It is a Proth number, since it is equal to 4155 ⋅ 2¹⁴ + 1 and 4155 < 2¹⁴.

Almost surely, 2^68075521 is an apocalyptic number.

It is an amenable number.

68075521 is a deficient number, since it is larger than the sum of its proper divisors (820271).

68075521 is an equidigital number, since it uses as much as digits as its factorization.

68075521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820270.

The product of its (nonzero) digits is 16800, while the sum is 34.

The square root of 68075521 is about 8250.7891137757. The cubic root of 68075521 is about 408.3165575597.

The spelling of 68075521 in words is "sixty-eight million, seventy-five thousand, five hundred twenty-one".