20363987 has 4 divisors (see below), whose sum is σ = 23273136. Its totient is φ = 17454840.

The previous prime is 20363971. The next prime is 20364013. The reversal of 20363987 is 78936302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78936302 = 2 ⋅39468151.

It is a cyclic number.

It is not a de Polignac number, because 20363987 - 2⁴ = 20363971 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20363987.

It is not an unprimeable number, because it can be changed into a prime (20363927) 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, 1454564 + ... + 1454577.

It is an arithmetic number, because the mean of its divisors is an integer number (5818284).

Almost surely, 2^20363987 is an apocalyptic number.

20363987 is a deficient number, since it is larger than the sum of its proper divisors (2909149).

20363987 is an equidigital number, since it uses as much as digits as its factorization.

20363987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2909148.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 20363987 is about 4512.6474491145. The cubic root of 20363987 is about 273.0785597774.

The spelling of 20363987 in words is "twenty million, three hundred sixty-three thousand, nine hundred eighty-seven".