20513565210 has 64 divisors (see below), whose sum is σ = 50880420864. Its totient is φ = 5287603200.

The previous prime is 20513565203. The next prime is 20513565227. The reversal of 20513565210 is 1256531502.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 806812 + ... + 831848.

It is an arithmetic number, because the mean of its divisors is an integer number (795006576).

Almost surely, 2^20513565210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20513565210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25440210432).

20513565210 is an abundant number, since it is smaller than the sum of its proper divisors (30366855654).

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

20513565210 is a wasteful number, since it uses less digits than its factorization.

20513565210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25959.

The product of its (nonzero) digits is 9000, while the sum is 30.

The spelling of 20513565210 in words is "twenty billion, five hundred thirteen million, five hundred sixty-five thousand, two hundred ten".