21331293 has 8 divisors (see below), whose sum is σ = 28491456. Its totient is φ = 14196000.

The previous prime is 21331283. The next prime is 21331309. The reversal of 21331293 is 39213312.

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

It is not a de Polignac number, because 21331293 - 2⁹ = 21330781 is a prime.

It is a super-2 number, since 2×21331293² = 910048122103698, which contains 22 as substring.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4113 + ... + 7718.

It is an arithmetic number, because the mean of its divisors is an integer number (3561432).

Almost surely, 2^21331293 is an apocalyptic number.

It is an amenable number.

21331293 is a deficient number, since it is larger than the sum of its proper divisors (7160163).

21331293 is a wasteful number, since it uses less digits than its factorization.

21331293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12435.

The product of its digits is 972, while the sum is 24.

The square root of 21331293 is about 4618.5812756733. The cubic root of 21331293 is about 277.3356676576.

The spelling of 21331293 in words is "twenty-one million, three hundred thirty-one thousand, two hundred ninety-three".