68699621 has 2 divisors, whose sum is σ = 68699622. Its totient is φ = 68699620.

The previous prime is 68699599. The next prime is 68699623. The reversal of 68699621 is 12699686.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65772100 + 2927521 = 8110^2 + 1711^2 .

It is a cyclic number.

It is not a de Polignac number, because 68699621 - 2⁶ = 68699557 is a prime.

It is a Sophie Germain prime.

Together with 68699623, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68699623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34349810 + 34349811.

It is an arithmetic number, because the mean of its divisors is an integer number (34349811).

Almost surely, 2^68699621 is an apocalyptic number.

It is an amenable number.

68699621 is a deficient number, since it is larger than the sum of its proper divisors (1).

68699621 is an equidigital number, since it uses as much as digits as its factorization.

68699621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 47.

The square root of 68699621 is about 8288.5234511341. The cubic root of 68699621 is about 409.5605463968.

The spelling of 68699621 in words is "sixty-eight million, six hundred ninety-nine thousand, six hundred twenty-one".