20516550 has 24 divisors (see below), whose sum is σ = 50881416. Its totient is φ = 5471040.

The previous prime is 20516549. The next prime is 20516591. The reversal of 20516550 is 5561502.

It is a self number, because there is not a number n which added to its sum of digits gives 20516550.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 68239 + ... + 68538.

It is an arithmetic number, because the mean of its divisors is an integer number (2120059).

Almost surely, 2^20516550 is an apocalyptic number.

20516550 is an abundant number, since it is smaller than the sum of its proper divisors (30364866).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20516550 is a wasteful number, since it uses less digits than its factorization.

20516550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136792 (or 136787 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 20516550 is about 4529.5198421025. The cubic root of 20516550 is about 273.7588141696.

The spelling of 20516550 in words is "twenty million, five hundred sixteen thousand, five hundred fifty".