21027946 has 32 divisors (see below), whose sum is σ = 36020160. Its totient is φ = 9144576.

The previous prime is 21027943. The next prime is 21027947. The reversal of 21027946 is 64972012.

21027946 = 1043² + 1044² + ... + 1061².

It is not an unprimeable number, because it can be changed into a prime (21027943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27400 + ... + 28156.

It is an arithmetic number, because the mean of its divisors is an integer number (1125630).

Almost surely, 2^21027946 is an apocalyptic number.

21027946 is a deficient number, since it is larger than the sum of its proper divisors (14992214).

21027946 is a wasteful number, since it uses less digits than its factorization.

21027946 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 838.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 21027946 is about 4585.6238397845. The cubic root of 21027946 is about 276.0147457640.

Adding to 21027946 its reverse (64972012), we get a palindrome (85999958).

The spelling of 21027946 in words is "twenty-one million, twenty-seven thousand, nine hundred forty-six".