21482021 has 4 divisors (see below), whose sum is σ = 23434944. Its totient is φ = 19529100.

The previous prime is 21481963. The next prime is 21482029. The reversal of 21482021 is 12028412.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21482021 - 2¹⁰ = 21480997 is a prime.

It is a super-2 number, since 2×21482021² = 922954452488882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21481984 and 21482002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21482029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 976445 + ... + 976466.

It is an arithmetic number, because the mean of its divisors is an integer number (5858736).

Almost surely, 2^21482021 is an apocalyptic number.

It is an amenable number.

21482021 is a deficient number, since it is larger than the sum of its proper divisors (1952923).

21482021 is a wasteful number, since it uses less digits than its factorization.

21482021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1952922.

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 21482021 is about 4634.8701168425. The cubic root of 21482021 is about 277.9873577399.

The spelling of 21482021 in words is "twenty-one million, four hundred eighty-two thousand, twenty-one".