21027842 has 32 divisors (see below), whose sum is σ = 37169280. Its totient is φ = 8821120.

The previous prime is 21027841. The next prime is 21027863. The reversal of 21027842 is 24872012.

It is not an unprimeable number, because it can be changed into a prime (21027841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13958 + ... + 15390.

It is an arithmetic number, because the mean of its divisors is an integer number (1161540).

Almost surely, 2^21027842 is an apocalyptic number.

21027842 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21027842 is a deficient number, since it is larger than the sum of its proper divisors (16141438).

21027842 is a wasteful number, since it uses less digits than its factorization.

21027842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1498.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 21027842 is about 4585.6124999830. The cubic root of 21027842 is about 276.0142907254.

Adding to 21027842 its reverse (24872012), we get a palindrome (45899854).

The spelling of 21027842 in words is "twenty-one million, twenty-seven thousand, eight hundred forty-two".