21377224 has 16 divisors (see below), whose sum is σ = 43726320. Its totient is φ = 9716880.

The previous prime is 21377201. The next prime is 21377233. The reversal of 21377224 is 42277312.

It is a junction number, because it is equal to n+sod(n) for n = 21377192 and 21377201.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121374 + ... + 121549.

It is an arithmetic number, because the mean of its divisors is an integer number (2732895).

Almost surely, 2^21377224 is an apocalyptic number.

It is an amenable number.

21377224 is an abundant number, since it is smaller than the sum of its proper divisors (22349096).

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

21377224 is a wasteful number, since it uses less digits than its factorization.

21377224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242940 (or 242936 counting only the distinct ones).

The product of its digits is 4704, while the sum is 28.

The square root of 21377224 is about 4623.5510162644. The cubic root of 21377224 is about 277.5345800048.

The spelling of 21377224 in words is "twenty-one million, three hundred seventy-seven thousand, two hundred twenty-four".