21463620 has 24 divisors (see below), whose sum is σ = 60098304. Its totient is φ = 5723616.

The previous prime is 21463613. The next prime is 21463621. The reversal of 21463620 is 2636412.

It is not an unprimeable number, because it can be changed into a prime (21463621) 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, 178804 + ... + 178923.

It is an arithmetic number, because the mean of its divisors is an integer number (2504096).

Almost surely, 2^21463620 is an apocalyptic number.

21463620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21463620 is an abundant number, since it is smaller than the sum of its proper divisors (38634684).

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

21463620 is a wasteful number, since it uses less digits than its factorization.

21463620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357739 (or 357737 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 21463620 is about 4632.8846305515. The cubic root of 21463620 is about 277.9079625626.

The spelling of 21463620 in words is "twenty-one million, four hundred sixty-three thousand, six hundred twenty".