21530016810 has 64 divisors (see below), whose sum is σ = 57940185600. Its totient is φ = 5688657216.

The previous prime is 21530016787. The next prime is 21530016821. The reversal of 21530016810 is 1861003512.

21530016810 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×21530016810² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 336354 + ... + 395213.

It is an arithmetic number, because the mean of its divisors is an integer number (905315400).

Almost surely, 2^21530016810 is an apocalyptic number.

21530016810 is an abundant number, since it is smaller than the sum of its proper divisors (36410168790).

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

21530016810 is a wasteful number, since it uses less digits than its factorization.

21530016810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 731692 (or 731686 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The spelling of 21530016810 in words is "twenty-one billion, five hundred thirty million, sixteen thousand, eight hundred ten".