20408632385 has 8 divisors (see below), whose sum is σ = 24577514856. Its totient is φ = 16268801920.

The previous prime is 20408632381. The next prime is 20408632403. The reversal of 20408632385 is 58323680402.

It can be written as a sum of positive squares in 4 ways, for example, as 7577180209 + 12831452176 = 87047^2 + 113276^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20408632385 - 2² = 20408632381 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20408632381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7261454 + ... + 7264263.

It is an arithmetic number, because the mean of its divisors is an integer number (3072189357).

Almost surely, 2^20408632385 is an apocalyptic number.

It is an amenable number.

20408632385 is a deficient number, since it is larger than the sum of its proper divisors (4168882471).

20408632385 is a wasteful number, since it uses less digits than its factorization.

20408632385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14526003.

The product of its (nonzero) digits is 276480, while the sum is 41.

The spelling of 20408632385 in words is "twenty billion, four hundred eight million, six hundred thirty-two thousand, three hundred eighty-five".