21094587 has 24 divisors (see below), whose sum is σ = 32288256. Its totient is φ = 13756392.

The previous prime is 21094559. The next prime is 21094589. The reversal of 21094587 is 78549012.

It is not a de Polignac number, because 21094587 - 2⁶ = 21094523 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (21094589) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10498 + ... + 12344.

It is an arithmetic number, because the mean of its divisors is an integer number (1345344).

Almost surely, 2^21094587 is an apocalyptic number.

21094587 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21094587 is a deficient number, since it is larger than the sum of its proper divisors (11193669).

21094587 is an equidigital number, since it uses as much as digits as its factorization.

21094587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1909 (or 1897 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 21094587 is about 4592.8843878330. The cubic root of 21094587 is about 276.3060169089.

The spelling of 21094587 in words is "twenty-one million, ninety-four thousand, five hundred eighty-seven".