20550015 has 24 divisors (see below), whose sum is σ = 35758320. Its totient is φ = 10917504.

The previous prime is 20550007. The next prime is 20550037. The reversal of 20550015 is 51005502.

It is not a de Polignac number, because 20550015 - 2³ = 20550007 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20550015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13356 + ... + 14814.

It is an arithmetic number, because the mean of its divisors is an integer number (1489930).

Almost surely, 2^20550015 is an apocalyptic number.

20550015 is a deficient number, since it is larger than the sum of its proper divisors (15208305).

20550015 is a wasteful number, since it uses less digits than its factorization.

20550015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783 (or 1780 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 18.

The square root of 20550015 is about 4533.2124371134. The cubic root of 20550015 is about 273.9075780072.

Adding to 20550015 its reverse (51005502), we get a palindrome (71555517).

The spelling of 20550015 in words is "twenty million, five hundred fifty thousand, fifteen".