68156987 has 4 divisors (see below), whose sum is σ = 68324040. Its totient is φ = 67989936.

The previous prime is 68156951. The next prime is 68156999. The reversal of 68156987 is 78965186.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78965186 = 2 ⋅39482593.

It is a cyclic number.

It is not a de Polignac number, because 68156987 - 2¹⁰ = 68155963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68156917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82913 + ... + 83730.

It is an arithmetic number, because the mean of its divisors is an integer number (17081010).

Almost surely, 2^68156987 is an apocalyptic number.

68156987 is a deficient number, since it is larger than the sum of its proper divisors (167053).

68156987 is a wasteful number, since it uses less digits than its factorization.

68156987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167052.

The product of its digits is 725760, while the sum is 50.

The square root of 68156987 is about 8255.7244987948. The cubic root of 68156987 is about 408.4793701538.

The spelling of 68156987 in words is "sixty-eight million, one hundred fifty-six thousand, nine hundred eighty-seven".