21472297 has 24 divisors (see below), whose sum is σ = 27349056. Its totient is φ = 16500000.

The previous prime is 21472291. The next prime is 21472313. The reversal of 21472297 is 79227412.

It is a happy number.

It is not a de Polignac number, because 21472297 - 2¹⁵ = 21439529 is a prime.

It is a super-2 number, since 2×21472297² = 922119076912418, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21472291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 85422 + ... + 85672.

It is an arithmetic number, because the mean of its divisors is an integer number (1139544).

Almost surely, 2^21472297 is an apocalyptic number.

It is an amenable number.

21472297 is a deficient number, since it is larger than the sum of its proper divisors (5876759).

21472297 is a wasteful number, since it uses less digits than its factorization.

21472297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 370 counting only the distinct ones).

The product of its digits is 14112, while the sum is 34.

The square root of 21472297 is about 4633.8209935214. The cubic root of 21472297 is about 277.9454070464.

It can be divided in two parts, 2147 and 2297, that added together give a palindrome (4444).

The spelling of 21472297 in words is "twenty-one million, four hundred seventy-two thousand, two hundred ninety-seven".