20506121650 has 96 divisors (see below), whose sum is σ = 47228227200. Its totient is φ = 6463134720.

The previous prime is 20506121551. The next prime is 20506121651. The reversal of 20506121650 is 5612160502.

It is not an unprimeable number, because it can be changed into a prime (20506121651) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 215776 + ... + 295924.

It is an arithmetic number, because the mean of its divisors is an integer number (491960700).

Almost surely, 2^20506121650 is an apocalyptic number.

20506121650 is an abundant number, since it is smaller than the sum of its proper divisors (26722105550).

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

20506121650 is a wasteful number, since it uses less digits than its factorization.

20506121650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80228 (or 80223 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The spelling of 20506121650 in words is "twenty billion, five hundred six million, one hundred twenty-one thousand, six hundred fifty".