21173460 has 96 divisors (see below), whose sum is σ = 73930752. Its totient is φ = 4398720.

The previous prime is 21173437. The next prime is 21173473. The reversal of 21173460 is 6437112.

It is a self number, because there is not a number n which added to its sum of digits gives 21173460.

It is a congruent number.

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, 2329 + ... + 6911.

It is an arithmetic number, because the mean of its divisors is an integer number (770112).

Almost surely, 2^21173460 is an apocalyptic number.

21173460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21173460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36965376).

21173460 is an abundant number, since it is smaller than the sum of its proper divisors (52757292).

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

21173460 is a wasteful number, since it uses less digits than its factorization.

21173460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4613 (or 4611 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 21173460 is about 4601.4628108896. The cubic root of 21173460 is about 276.6499594756.

The spelling of 21173460 in words is "twenty-one million, one hundred seventy-three thousand, four hundred sixty".