21366469 has 4 divisors (see below), whose sum is σ = 22491040. Its totient is φ = 20241900.

The previous prime is 21366463. The next prime is 21366487. The reversal of 21366469 is 96466312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21366469 - 2¹³ = 21358277 is a prime.

It is a super-2 number, since 2×21366469² = 913051995055922, which contains 22 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 (21366463) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 562257 + ... + 562294.

It is an arithmetic number, because the mean of its divisors is an integer number (5622760).

Almost surely, 2^21366469 is an apocalyptic number.

It is an amenable number.

21366469 is a deficient number, since it is larger than the sum of its proper divisors (1124571).

21366469 is a wasteful number, since it uses less digits than its factorization.

21366469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124570.

The product of its digits is 46656, while the sum is 37.

The square root of 21366469 is about 4622.3878028569. The cubic root of 21366469 is about 277.4880291349.

The spelling of 21366469 in words is "twenty-one million, three hundred sixty-six thousand, four hundred sixty-nine".