20506255 has 32 divisors (see below), whose sum is σ = 31334400. Its totient is φ = 12771360.

The previous prime is 20506249. The next prime is 20506261. The reversal of 20506255 is 55260502.

It is an interprime number because it is at equal distance from previous prime (20506249) and next prime (20506261).

It is not a de Polignac number, because 20506255 - 2³ = 20506247 is a prime.

It is a partition number, being equal to the number of ways a set of 82 identical objects can be partitioned into subset.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18322 + ... + 19408.

It is an arithmetic number, because the mean of its divisors is an integer number (979200).

Almost surely, 2^20506255 is an apocalyptic number.

20506255 is a deficient number, since it is larger than the sum of its proper divisors (10828145).

20506255 is a wasteful number, since it uses less digits than its factorization.

20506255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124 (or 1110 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 20506255 is about 4528.3832655817. The cubic root of 20506255 is about 273.7130166951.

Adding to 20506255 its reverse (55260502), we get a palindrome (75766757).

The spelling of 20506255 in words is "twenty million, five hundred six thousand, two hundred fifty-five".