20405147 has 8 divisors (see below), whose sum is σ = 23616000. Its totient is φ = 17268264.

The previous prime is 20405141. The next prime is 20405153. The reversal of 20405147 is 74150402.

It is an interprime number because it is at equal distance from previous prime (20405141) and next prime (20405153).

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

It is a cyclic number.

It is not a de Polignac number, because 20405147 - 2¹⁰ = 20404123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20405141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17897 + ... + 19002.

It is an arithmetic number, because the mean of its divisors is an integer number (2952000).

Almost surely, 2^20405147 is an apocalyptic number.

20405147 is a deficient number, since it is larger than the sum of its proper divisors (3210853).

20405147 is an equidigital number, since it uses as much as digits as its factorization.

20405147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36985.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 20405147 is about 4517.2056627964. The cubic root of 20405147 is about 273.2624194713.

Adding to 20405147 its reverse (74150402), we get a palindrome (94555549).

The spelling of 20405147 in words is "twenty million, four hundred five thousand, one hundred forty-seven".