21448197 has 24 divisors (see below), whose sum is σ = 32930040. Its totient is φ = 13426560.

The previous prime is 21448171. The next prime is 21448247. The reversal of 21448197 is 79184412.

21448197 is a `hidden beast` number, since 21 + 448 + 197 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 9400356 + 12047841 = 3066^2 + 3471^2 .

It is not a de Polignac number, because 21448197 - 2¹¹ = 21446149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21448127) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8547 + ... + 10767.

It is an arithmetic number, because the mean of its divisors is an integer number (1372085).

Almost surely, 2^21448197 is an apocalyptic number.

It is an amenable number.

21448197 is a deficient number, since it is larger than the sum of its proper divisors (11481843).

21448197 is a wasteful number, since it uses less digits than its factorization.

21448197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2293 (or 2290 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 21448197 is about 4631.2198177154. The cubic root of 21448197 is about 277.8413816604.

The spelling of 21448197 in words is "twenty-one million, four hundred forty-eight thousand, one hundred ninety-seven".