21473365 has 8 divisors (see below), whose sum is σ = 25852248. Its totient is φ = 17122560.

The previous prime is 21473351. The next prime is 21473393. The reversal of 21473365 is 56337412.

It can be written as a sum of positive squares in 4 ways, for example, as 734449 + 20738916 = 857^2 + 4554^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21473365 - 2¹³ = 21465173 is a prime.

It is a super-2 number, since 2×21473365² = 922210808846450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5296 + ... + 8425.

It is an arithmetic number, because the mean of its divisors is an integer number (3231531).

Almost surely, 2^21473365 is an apocalyptic number.

It is an amenable number.

21473365 is a deficient number, since it is larger than the sum of its proper divisors (4378883).

21473365 is a wasteful number, since it uses less digits than its factorization.

21473365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14039.

The product of its digits is 15120, while the sum is 31.

The square root of 21473365 is about 4633.9362317581. The cubic root of 21473365 is about 277.9500151665.

The spelling of 21473365 in words is "twenty-one million, four hundred seventy-three thousand, three hundred sixty-five".