21682368 has 42 divisors (see below), whose sum is σ = 62150244. Its totient is φ = 7227264.

The previous prime is 21682357. The next prime is 21682379. The reversal of 21682368 is 86328612.

21682368 is a `hidden beast` number, since 216 + 82 + 368 = 666.

It is an interprime number because it is at equal distance from previous prime (21682357) and next prime (21682379).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18246 + ... + 19397.

Almost surely, 2^21682368 is an apocalyptic number.

It is an amenable number.

21682368 is an abundant number, since it is smaller than the sum of its proper divisors (40467876).

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

21682368 is a wasteful number, since it uses less digits than its factorization.

21682368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37661 (or 37648 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 21682368 is about 4656.4329695594. The cubic root of 21682368 is about 278.8488795046.

The spelling of 21682368 in words is "twenty-one million, six hundred eighty-two thousand, three hundred sixty-eight".