20405743 has 2 divisors, whose sum is σ = 20405744. Its totient is φ = 20405742.

The previous prime is 20405713. The next prime is 20405767. The reversal of 20405743 is 34750402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20405743 - 2¹³ = 20397551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20405713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10202871 + 10202872.

It is an arithmetic number, because the mean of its divisors is an integer number (10202872).

Almost surely, 2^20405743 is an apocalyptic number.

20405743 is a deficient number, since it is larger than the sum of its proper divisors (1).

20405743 is an equidigital number, since it uses as much as digits as its factorization.

20405743 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 25.

The square root of 20405743 is about 4517.2716323020. The cubic root of 20405743 is about 273.2650799572.

The spelling of 20405743 in words is "twenty million, four hundred five thousand, seven hundred forty-three".