20723771 has 2 divisors, whose sum is σ = 20723772. Its totient is φ = 20723770.

The previous prime is 20723753. The next prime is 20723783. The reversal of 20723771 is 17732702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20723771 - 2⁶ = 20723707 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20723711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10361885 + 10361886.

It is an arithmetic number, because the mean of its divisors is an integer number (10361886).

Almost surely, 2^20723771 is an apocalyptic number.

20723771 is a deficient number, since it is larger than the sum of its proper divisors (1).

20723771 is an equidigital number, since it uses as much as digits as its factorization.

20723771 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4116, while the sum is 29.

The square root of 20723771 is about 4552.3368724206. The cubic root of 20723771 is about 274.6774002218.

The spelling of 20723771 in words is "twenty million, seven hundred twenty-three thousand, seven hundred seventy-one".