68761661 has 2 divisors, whose sum is σ = 68761662. Its totient is φ = 68761660.

The previous prime is 68761657. The next prime is 68761663. The reversal of 68761661 is 16616786.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64480900 + 4280761 = 8030^2 + 2069^2 .

It is a cyclic number.

It is not a de Polignac number, because 68761661 - 2² = 68761657 is a prime.

Together with 68761663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68761663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34380830 + 34380831.

It is an arithmetic number, because the mean of its divisors is an integer number (34380831).

Almost surely, 2^68761661 is an apocalyptic number.

It is an amenable number.

68761661 is a deficient number, since it is larger than the sum of its proper divisors (1).

68761661 is an equidigital number, since it uses as much as digits as its factorization.

68761661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 41.

The square root of 68761661 is about 8292.2651308313. The cubic root of 68761661 is about 409.6837954584.

The spelling of 68761661 in words is "sixty-eight million, seven hundred sixty-one thousand, six hundred sixty-one".