21354849 has 6 divisors (see below), whose sum is σ = 30845906. Its totient is φ = 14236560.

The previous prime is 21354847. The next prime is 21354857. The reversal of 21354849 is 94845312.

It can be written as a sum of positive squares in only one way, i.e., 19580625 + 1774224 = 4425^2 + 1332^2 .

It is not a de Polignac number, because 21354849 - 2¹ = 21354847 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21354847) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1186372 + ... + 1186389.

Almost surely, 2^21354849 is an apocalyptic number.

It is an amenable number.

21354849 is a deficient number, since it is larger than the sum of its proper divisors (9491057).

21354849 is a wasteful number, since it uses less digits than its factorization.

21354849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2372767 (or 2372764 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 21354849 is about 4621.1307057905. The cubic root of 21354849 is about 277.4377167256.

The spelling of 21354849 in words is "twenty-one million, three hundred fifty-four thousand, eight hundred forty-nine".