68509961 has 8 divisors (see below), whose sum is σ = 73893960. Its totient is φ = 63142272.

The previous prime is 68509957. The next prime is 68509963. The reversal of 68509961 is 16990586.

It can be written as a sum of positive squares in 4 ways, for example, as 5148361 + 63361600 = 2269^2 + 7960^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 68509961 - 2² = 68509957 is a prime.

It is a super-2 number, since 2×68509961² = 9387229512443042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68509963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5501 + ... + 12933.

It is an arithmetic number, because the mean of its divisors is an integer number (9236745).

Almost surely, 2^68509961 is an apocalyptic number.

It is an amenable number.

68509961 is a deficient number, since it is larger than the sum of its proper divisors (5383999).

68509961 is a wasteful number, since it uses less digits than its factorization.

68509961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8155.

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 68509961 is about 8277.0744227656. The cubic root of 68509961 is about 409.1833058653.

The spelling of 68509961 in words is "sixty-eight million, five hundred nine thousand, nine hundred sixty-one".