21472380 has 36 divisors (see below), whose sum is σ = 65133432. Its totient is φ = 5725920.

The previous prime is 21472379. The next prime is 21472391. The reversal of 21472380 is 8327412.

21472380 is a `hidden beast` number, since 214 + 72 + 380 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×21472380² = 922126205728800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59466 + ... + 59825.

It is an arithmetic number, because the mean of its divisors is an integer number (1809262).

Almost surely, 2^21472380 is an apocalyptic number.

21472380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21472380 is an abundant number, since it is smaller than the sum of its proper divisors (43661052).

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

21472380 is a wasteful number, since it uses less digits than its factorization.

21472380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119306 (or 119301 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 21472380 is about 4633.8299494047. The cubic root of 21472380 is about 277.9457651736.

Adding to 21472380 its reverse (8327412), we get a palindrome (29799792).

The spelling of 21472380 in words is "twenty-one million, four hundred seventy-two thousand, three hundred eighty".