21221670560 has 48 divisors (see below), whose sum is σ = 50145026400. Its totient is φ = 8487173376.

The previous prime is 21221670557. The next prime is 21221670577. The reversal of 21221670560 is 6507612212.

It is a super-3 number, since 3×21221670560³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1551431 + ... + 1565049.

It is an arithmetic number, because the mean of its divisors is an integer number (1044688050).

Almost surely, 2^21221670560 is an apocalyptic number.

21221670560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221670560 is an abundant number, since it is smaller than the sum of its proper divisors (28923355840).

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

21221670560 is a wasteful number, since it uses less digits than its factorization.

21221670560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23373 (or 23365 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The spelling of 21221670560 in words is "twenty-one billion, two hundred twenty-one million, six hundred seventy thousand, five hundred sixty".