68644661 has 2 divisors, whose sum is σ = 68644662. Its totient is φ = 68644660.

The previous prime is 68644621. The next prime is 68644787. The reversal of 68644661 is 16644686.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41667025 + 26977636 = 6455^2 + 5194^2 .

It is a cyclic number.

It is not a de Polignac number, because 68644661 - 2²² = 64450357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68644621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34322330 + 34322331.

It is an arithmetic number, because the mean of its divisors is an integer number (34322331).

Almost surely, 2^68644661 is an apocalyptic number.

It is an amenable number.

68644661 is a deficient number, since it is larger than the sum of its proper divisors (1).

68644661 is an equidigital number, since it uses as much as digits as its factorization.

68644661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 165888, while the sum is 41.

The square root of 68644661 is about 8285.2073601087. The cubic root of 68644661 is about 409.4513005110.

The spelling of 68644661 in words is "sixty-eight million, six hundred forty-four thousand, six hundred sixty-one".