21106425 has 12 divisors (see below), whose sum is σ = 34896080. Its totient is φ = 11256720.

The previous prime is 21106411. The next prime is 21106429. The reversal of 21106425 is 52460112.

It is not a de Polignac number, because 21106425 - 2⁶ = 21106361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21106429) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 140635 + ... + 140784.

Almost surely, 2^21106425 is an apocalyptic number.

21106425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21106425 is a deficient number, since it is larger than the sum of its proper divisors (13789655).

21106425 is a wasteful number, since it uses less digits than its factorization.

21106425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281432 (or 281427 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 21106425 is about 4594.1729397140. The cubic root of 21106425 is about 276.3576936567.

Adding to 21106425 its reverse (52460112), we get a palindrome (73566537).

The spelling of 21106425 in words is "twenty-one million, one hundred six thousand, four hundred twenty-five".