20001405 has 32 divisors (see below), whose sum is σ = 33022080. Its totient is φ = 10333440.

The previous prime is 20001389. The next prime is 20001439. The reversal of 20001405 is 50410002.

It is not a de Polignac number, because 20001405 - 2⁴ = 20001389 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 110415 + ... + 110595.

It is an arithmetic number, because the mean of its divisors is an integer number (1031940).

Almost surely, 2^20001405 is an apocalyptic number.

It is an amenable number.

20001405 is a deficient number, since it is larger than the sum of its proper divisors (13020675).

20001405 is a wasteful number, since it uses less digits than its factorization.

20001405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381.

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 20001405 is about 4472.2930360163. The cubic root of 20001405 is about 271.4481177719.

Adding to 20001405 its reverse (50410002), we get a palindrome (70411407).

The spelling of 20001405 in words is "twenty million, one thousand, four hundred five".