20401439 has 2 divisors, whose sum is σ = 20401440. Its totient is φ = 20401438.

The previous prime is 20401429. The next prime is 20401453. The reversal of 20401439 is 93410402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20401439 - 2²⁰ = 19352863 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20401429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10200719 + 10200720.

It is an arithmetic number, because the mean of its divisors is an integer number (10200720).

Almost surely, 2^20401439 is an apocalyptic number.

20401439 is a deficient number, since it is larger than the sum of its proper divisors (1).

20401439 is an equidigital number, since it uses as much as digits as its factorization.

20401439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 20401439 is about 4516.7952134229. The cubic root of 20401439 is about 273.2458661570.

The spelling of 20401439 in words is "twenty million, four hundred one thousand, four hundred thirty-nine".