20421512573 has 32 divisors (see below), whose sum is σ = 26587422720. Its totient is φ = 15209631360.

The previous prime is 20421512563. The next prime is 20421512597. The reversal of 20421512573 is 37521512402.

It is not a de Polignac number, because 20421512573 - 2¹⁰ = 20421511549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421512513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2931068 + ... + 2938026.

It is an arithmetic number, because the mean of its divisors is an integer number (830856960).

Almost surely, 2^20421512573 is an apocalyptic number.

20421512573 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

20421512573 is a deficient number, since it is larger than the sum of its proper divisors (6165910147).

20421512573 is a wasteful number, since it uses less digits than its factorization.

20421512573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8657.

The product of its (nonzero) digits is 16800, while the sum is 32.

The spelling of 20421512573 in words is "twenty billion, four hundred twenty-one million, five hundred twelve thousand, five hundred seventy-three".