68401985 has 4 divisors (see below), whose sum is σ = 82082388. Its totient is φ = 54721584.

The previous prime is 68401979. The next prime is 68401987. The reversal of 68401985 is 58910486.

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 15272464 + 53129521 = 3908^2 + 7289^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68401985 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68401987) 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, 6840194 + ... + 6840203.

It is an arithmetic number, because the mean of its divisors is an integer number (20520597).

Almost surely, 2^68401985 is an apocalyptic number.

It is an amenable number.

68401985 is a deficient number, since it is larger than the sum of its proper divisors (13680403).

68401985 is a wasteful number, since it uses less digits than its factorization.

68401985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13680402.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 68401985 is about 8270.5492562465. The cubic root of 68401985 is about 408.9682266392.

The spelling of 68401985 in words is "sixty-eight million, four hundred one thousand, nine hundred eighty-five".