21290093 has 8 divisors (see below), whose sum is σ = 23456736. Its totient is φ = 19162000.

The previous prime is 21290083. The next prime is 21290119. The reversal of 21290093 is 39009212.

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

It is not a de Polignac number, because 21290093 - 2¹⁰ = 21289069 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21290083) 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 7 ways as a sum of consecutive naturals, for example, 8471 + ... + 10692.

It is an arithmetic number, because the mean of its divisors is an integer number (2932092).

Almost surely, 2^21290093 is an apocalyptic number.

It is an amenable number.

21290093 is a deficient number, since it is larger than the sum of its proper divisors (2166643).

21290093 is a wasteful number, since it uses less digits than its factorization.

21290093 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19275.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 21290093 is about 4614.1188757985. The cubic root of 21290093 is about 277.1570006674.

The spelling of 21290093 in words is "twenty-one million, two hundred ninety thousand, ninety-three".