20690771 has 2 divisors, whose sum is σ = 20690772. Its totient is φ = 20690770.

The previous prime is 20690767. The next prime is 20690797. The reversal of 20690771 is 17709602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20690771 - 2² = 20690767 is a prime.

It is not a weakly prime, because it can be changed into another prime (20690701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10345385 + 10345386.

It is an arithmetic number, because the mean of its divisors is an integer number (10345386).

Almost surely, 2^20690771 is an apocalyptic number.

20690771 is a deficient number, since it is larger than the sum of its proper divisors (1).

20690771 is an equidigital number, since it uses as much as digits as its factorization.

20690771 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5292, while the sum is 32.

The square root of 20690771 is about 4548.7109162927. The cubic root of 20690771 is about 274.5315263563.

The spelling of 20690771 in words is "twenty million, six hundred ninety thousand, seven hundred seventy-one".