21023107 has 6 divisors (see below), whose sum is σ = 24455508. Its totient is φ = 18019764.

The previous prime is 21023099. The next prime is 21023111. The reversal of 21023107 is 70132012.

It is a happy number.

It is not a de Polignac number, because 21023107 - 2³ = 21023099 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21023117) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 214473 + ... + 214570.

It is an arithmetic number, because the mean of its divisors is an integer number (4075918).

Almost surely, 2^21023107 is an apocalyptic number.

21023107 is a deficient number, since it is larger than the sum of its proper divisors (3432401).

21023107 is an equidigital number, since it uses as much as digits as its factorization.

21023107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429057 (or 429050 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 21023107 is about 4585.0961821973. The cubic root of 21023107 is about 275.9935717539.

Adding to 21023107 its reverse (70132012), we get a palindrome (91155119).

The spelling of 21023107 in words is "twenty-one million, twenty-three thousand, one hundred seven".