20361647 has 4 divisors (see below), whose sum is σ = 21246960. Its totient is φ = 19476336.

The previous prime is 20361641. The next prime is 20361659. The reversal of 20361647 is 74616302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74616302 = 2 ⋅37308151.

It is a cyclic number.

It is not a de Polignac number, because 20361647 - 2¹⁰ = 20360623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20361641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 442622 + ... + 442667.

It is an arithmetic number, because the mean of its divisors is an integer number (5311740).

Almost surely, 2^20361647 is an apocalyptic number.

20361647 is a deficient number, since it is larger than the sum of its proper divisors (885313).

20361647 is an equidigital number, since it uses as much as digits as its factorization.

20361647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885312.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 20361647 is about 4512.3881703595. The cubic root of 20361647 is about 273.0680996727.

Adding to 20361647 its reverse (74616302), we get a palindrome (94977949).

The spelling of 20361647 in words is "twenty million, three hundred sixty-one thousand, six hundred forty-seven".