68311513 has 2 divisors, whose sum is σ = 68311514. Its totient is φ = 68311512.

The previous prime is 68311493. The next prime is 68311531. The reversal of 68311513 is 31511386.

Together with next prime (68311531) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63872064 + 4439449 = 7992^2 + 2107^2 .

It is a cyclic number.

It is not a de Polignac number, because 68311513 - 2²¹ = 66214361 is a prime.

It is not a weakly prime, because it can be changed into another prime (68311613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34155756 + 34155757.

It is an arithmetic number, because the mean of its divisors is an integer number (34155757).

Almost surely, 2^68311513 is an apocalyptic number.

It is an amenable number.

68311513 is a deficient number, since it is larger than the sum of its proper divisors (1).

68311513 is an equidigital number, since it uses as much as digits as its factorization.

68311513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 28.

The square root of 68311513 is about 8265.0779185680. The cubic root of 68311513 is about 408.7878395828.

Adding to 68311513 its reverse (31511386), we get a palindrome (99822899).

The spelling of 68311513 in words is "sixty-eight million, three hundred eleven thousand, five hundred thirteen".