21392469 has 36 divisors (see below), whose sum is σ = 36279360. Its totient is φ = 12111120.

The previous prime is 21392467. The next prime is 21392491. The reversal of 21392469 is 96429312.

It is not a de Polignac number, because 21392469 - 2¹ = 21392467 is a prime.

It is a super-2 number, since 2×21392469² = 915275459831922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21392467) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 78804 + ... + 79074.

It is an arithmetic number, because the mean of its divisors is an integer number (1007760).

Almost surely, 2^21392469 is an apocalyptic number.

It is an amenable number.

21392469 is a deficient number, since it is larger than the sum of its proper divisors (14886891).

21392469 is a wasteful number, since it uses less digits than its factorization.

21392469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470 (or 460 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 21392469 is about 4625.1993470552. The cubic root of 21392469 is about 277.6005381993.

The spelling of 21392469 in words is "twenty-one million, three hundred ninety-two thousand, four hundred sixty-nine".