21254460 has 48 divisors (see below), whose sum is σ = 59875200. Its totient is φ = 5633344.

The previous prime is 21254459. The next prime is 21254491. The reversal of 21254460 is 6445212.

It is a self number, because there is not a number n which added to its sum of digits gives 21254460.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9751 + ... + 11729.

It is an arithmetic number, because the mean of its divisors is an integer number (1247400).

Almost surely, 2^21254460 is an apocalyptic number.

21254460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21254460 is an abundant number, since it is smaller than the sum of its proper divisors (38620740).

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

21254460 is a wasteful number, since it uses less digits than its factorization.

21254460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2170 (or 2168 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 21254460 is about 4610.2559581871. The cubic root of 21254460 is about 277.0022894240.

Adding to 21254460 its reverse (6445212), we get a palindrome (27699672).

The spelling of 21254460 in words is "twenty-one million, two hundred fifty-four thousand, four hundred sixty".