20420867 has 2 divisors, whose sum is σ = 20420868. Its totient is φ = 20420866.

The previous prime is 20420861. The next prime is 20420891. The reversal of 20420867 is 76802402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20420867 - 2¹⁰ = 20419843 is a prime.

It is not a weakly prime, because it can be changed into another prime (20420861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10210433 + 10210434.

It is an arithmetic number, because the mean of its divisors is an integer number (10210434).

Almost surely, 2^20420867 is an apocalyptic number.

20420867 is a deficient number, since it is larger than the sum of its proper divisors (1).

20420867 is an equidigital number, since it uses as much as digits as its factorization.

20420867 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 20420867 is about 4518.9453415592. The cubic root of 20420867 is about 273.3325746889.

The spelling of 20420867 in words is "twenty million, four hundred twenty thousand, eight hundred sixty-seven".