21393097 has 16 divisors (see below), whose sum is σ = 24336000. Its totient is φ = 18627840.

The previous prime is 21393091. The next prime is 21393101. The reversal of 21393097 is 79039312.

It is not a de Polignac number, because 21393097 - 2²³ = 13004489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21393091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63313 + ... + 63649.

It is an arithmetic number, because the mean of its divisors is an integer number (1521000).

Almost surely, 2^21393097 is an apocalyptic number.

It is an amenable number.

21393097 is a deficient number, since it is larger than the sum of its proper divisors (2942903).

21393097 is a wasteful number, since it uses less digits than its factorization.

21393097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576.

The product of its (nonzero) digits is 10206, while the sum is 34.

The square root of 21393097 is about 4625.2672355227. The cubic root of 21393097 is about 277.6032545981.

The spelling of 21393097 in words is "twenty-one million, three hundred ninety-three thousand, ninety-seven".