420766691 has 2 divisors, whose sum is σ = 420766692. Its totient is φ = 420766690.

The previous prime is 420766681. The next prime is 420766721. The reversal of 420766691 is 196667024.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 420766691 - 2¹⁸ = 420504547 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (420766651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210383345 + 210383346.

It is an arithmetic number, because the mean of its divisors is an integer number (210383346).

Almost surely, 2^420766691 is an apocalyptic number.

420766691 is a deficient number, since it is larger than the sum of its proper divisors (1).

420766691 is an equidigital number, since it uses as much as digits as its factorization.

420766691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 41.

The square root of 420766691 is about 20512.5983483322. The cubic root of 420766691 is about 749.3426483163.

The spelling of 420766691 in words is "four hundred twenty million, seven hundred sixty-six thousand, six hundred ninety-one".