20210551521 has 16 divisors (see below), whose sum is σ = 27609167040. Its totient is φ = 13142926080.

The previous prime is 20210551519. The next prime is 20210551523. The reversal of 20210551521 is 12515501202.

It is an interprime number because it is at equal distance from previous prime (20210551519) and next prime (20210551523).

It is not a de Polignac number, because 20210551521 - 2¹ = 20210551519 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20210551491 and 20210551500.

It is not an unprimeable number, because it can be changed into a prime (20210551523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1151550 + ... + 1168968.

It is an arithmetic number, because the mean of its divisors is an integer number (1725572940).

Almost surely, 2^20210551521 is an apocalyptic number.

It is an amenable number.

20210551521 is a deficient number, since it is larger than the sum of its proper divisors (7398615519).

20210551521 is a wasteful number, since it uses less digits than its factorization.

20210551521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26896.

The product of its (nonzero) digits is 1000, while the sum is 24.

The spelling of 20210551521 in words is "twenty billion, two hundred ten million, five hundred fifty-one thousand, five hundred twenty-one".