21481682 has 24 divisors (see below), whose sum is σ = 34096716. Its totient is φ = 10142496.

The previous prime is 21481673. The next prime is 21481687. The reversal of 21481682 is 28618412.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21169201 + 312481 = 4601^2 + 559^2 .

It is a super-2 number, since 2×21481682² = 922925323098248, which contains 22 as substring.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21481687) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136748 + ... + 136904.

Almost surely, 2^21481682 is an apocalyptic number.

21481682 is a deficient number, since it is larger than the sum of its proper divisors (12615034).

21481682 is a wasteful number, since it uses less digits than its factorization.

21481682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 239 counting only the distinct ones).

The product of its digits is 6144, while the sum is 32.

The square root of 21481682 is about 4634.8335460942. The cubic root of 21481682 is about 277.9858954596.

The spelling of 21481682 in words is "twenty-one million, four hundred eighty-one thousand, six hundred eighty-two".