21859065460 has 24 divisors (see below), whose sum is σ = 48604275720. Its totient is φ = 8229295104.

The previous prime is 21859065439. The next prime is 21859065463. The reversal of 21859065460 is 6456095812.

It can be written as a sum of positive squares in 4 ways, for example, as 11747958544 + 10111106916 = 108388^2 + 100554^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21859065460.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21859065463) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32145345 + ... + 32146024.

It is an arithmetic number, because the mean of its divisors is an integer number (2025178155).

Almost surely, 2^21859065460 is an apocalyptic number.

21859065460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21859065460 is an abundant number, since it is smaller than the sum of its proper divisors (26745210260).

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

21859065460 is a wasteful number, since it uses less digits than its factorization.

21859065460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64291395 (or 64291393 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 46.

The spelling of 21859065460 in words is "twenty-one billion, eight hundred fifty-nine million, sixty-five thousand, four hundred sixty".