20742811 has 2 divisors, whose sum is σ = 20742812. Its totient is φ = 20742810.

The previous prime is 20742797. The next prime is 20742817. The reversal of 20742811 is 11824702.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20742811 - 2⁹ = 20742299 is a prime.

It is not a weakly prime, because it can be changed into another prime (20742817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10371405 + 10371406.

It is an arithmetic number, because the mean of its divisors is an integer number (10371406).

Almost surely, 2^20742811 is an apocalyptic number.

20742811 is the 2630-th hex number.

20742811 is a deficient number, since it is larger than the sum of its proper divisors (1).

20742811 is an equidigital number, since it uses as much as digits as its factorization.

20742811 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 20742811 is about 4554.4276259482. The cubic root of 20742811 is about 274.7614945833.

The spelling of 20742811 in words is "twenty million, seven hundred forty-two thousand, eight hundred eleven".