68069821 has 2 divisors, whose sum is σ = 68069822. Its totient is φ = 68069820.

The previous prime is 68069783. The next prime is 68069843. The reversal of 68069821 is 12896086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45077796 + 22992025 = 6714^2 + 4795^2 .

It is a cyclic number.

It is not a de Polignac number, because 68069821 - 2²³ = 59681213 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68069851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34034910 + 34034911.

It is an arithmetic number, because the mean of its divisors is an integer number (34034911).

Almost surely, 2^68069821 is an apocalyptic number.

It is an amenable number.

68069821 is a deficient number, since it is larger than the sum of its proper divisors (1).

68069821 is an equidigital number, since it uses as much as digits as its factorization.

68069821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 68069821 is about 8250.4436850390. The cubic root of 68069821 is about 408.3051610532.

The spelling of 68069821 in words is "sixty-eight million, sixty-nine thousand, eight hundred twenty-one".