21396484 has 6 divisors (see below), whose sum is σ = 37443854. Its totient is φ = 10698240.

The previous prime is 21396481. The next prime is 21396493. The reversal of 21396484 is 48469312.

It can be written as a sum of positive squares in only one way, i.e., 11410884 + 9985600 = 3378^2 + 3160^2 .

It is not an unprimeable number, because it can be changed into a prime (21396481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2674557 + ... + 2674564.

Almost surely, 2^21396484 is an apocalyptic number.

It is an amenable number.

21396484 is a deficient number, since it is larger than the sum of its proper divisors (16047370).

21396484 is a wasteful number, since it uses less digits than its factorization.

21396484 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5349125 (or 5349123 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 21396484 is about 4625.6333620381. The cubic root of 21396484 is about 277.6179040683.

The spelling of 21396484 in words is "twenty-one million, three hundred ninety-six thousand, four hundred eighty-four".