21048660 has 144 divisors (see below), whose sum is σ = 68245632. Its totient is φ = 5443200.

The previous prime is 21048649. The next prime is 21048701. The reversal of 21048660 is 6684012.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 296425 + ... + 296495.

It is an arithmetic number, because the mean of its divisors is an integer number (473928).

Almost surely, 2^21048660 is an apocalyptic number.

21048660 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 21048660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34122816).

21048660 is an abundant number, since it is smaller than the sum of its proper divisors (47196972).

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

21048660 is a wasteful number, since it uses less digits than its factorization.

21048660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 21048660 is about 4587.8818642158. The cubic root of 21048660 is about 276.1053473082.

The spelling of 21048660 in words is "twenty-one million, forty-eight thousand, six hundred sixty".