68609987 has 4 divisors (see below), whose sum is σ = 68655720. Its totient is φ = 68564256.

The previous prime is 68609953. The next prime is 68610001. The reversal of 68609987 is 78990686.

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

It is a cyclic number.

It is not a de Polignac number, because 68609987 - 2⁸ = 68609731 is a prime.

It is a super-2 number, since 2×68609987² = 9414660632280338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68609587) 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, 20537 + ... + 23642.

It is an arithmetic number, because the mean of its divisors is an integer number (17163930).

Almost surely, 2^68609987 is an apocalyptic number.

68609987 is a deficient number, since it is larger than the sum of its proper divisors (45733).

68609987 is a wasteful number, since it uses less digits than its factorization.

68609987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45732.

The product of its (nonzero) digits is 1306368, while the sum is 53.

The square root of 68609987 is about 8283.1145712226. The cubic root of 68609987 is about 409.3823478043.

It can be divided in two parts, 68609 and 987, that added together give a palindrome (69596).

The spelling of 68609987 in words is "sixty-eight million, six hundred nine thousand, nine hundred eighty-seven".