20919347 has 2 divisors, whose sum is σ = 20919348. Its totient is φ = 20919346.

The previous prime is 20919341. The next prime is 20919373. The reversal of 20919347 is 74391902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20919347 - 2⁴ = 20919331 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20919341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10459673 + 10459674.

It is an arithmetic number, because the mean of its divisors is an integer number (10459674).

Almost surely, 2^20919347 is an apocalyptic number.

20919347 is a deficient number, since it is larger than the sum of its proper divisors (1).

20919347 is an equidigital number, since it uses as much as digits as its factorization.

20919347 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 20919347 is about 4573.7672656138. The cubic root of 20919347 is about 275.5387652782.

The spelling of 20919347 in words is "twenty million, nine hundred nineteen thousand, three hundred forty-seven".