21273471 has 12 divisors (see below), whose sum is σ = 31720000. Its totient is φ = 13724640.

The previous prime is 21273463. The next prime is 21273479. The reversal of 21273471 is 17437212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21273463) and next prime (21273479).

It is not a de Polignac number, because 21273471 - 2³ = 21273463 is a prime.

It is a super-3 number, since 3×21273471³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21273479) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37846 + ... + 38403.

Almost surely, 2^21273471 is an apocalyptic number.

21273471 is a deficient number, since it is larger than the sum of its proper divisors (10446529).

21273471 is a wasteful number, since it uses less digits than its factorization.

21273471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76286 (or 76283 counting only the distinct ones).

The product of its digits is 2352, while the sum is 27.

The square root of 21273471 is about 4612.3173134554. The cubic root of 21273471 is about 277.0848528205.

The spelling of 21273471 in words is "twenty-one million, two hundred seventy-three thousand, four hundred seventy-one".