21060105 has 16 divisors (see below), whose sum is σ = 36759744. Its totient is φ = 10210880.

The previous prime is 21060097. The next prime is 21060131. The reversal of 21060105 is 50106012.

It is not a de Polignac number, because 21060105 - 2³ = 21060097 is a prime.

It is a super-2 number, since 2×21060105² = 887056045222050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63654 + ... + 63983.

It is an arithmetic number, because the mean of its divisors is an integer number (2297484).

Almost surely, 2^21060105 is an apocalyptic number.

It is an amenable number.

21060105 is a deficient number, since it is larger than the sum of its proper divisors (15699639).

21060105 is a wasteful number, since it uses less digits than its factorization.

21060105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127656.

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 21060105 is about 4589.1290023271. The cubic root of 21060105 is about 276.1553814216.

Adding to 21060105 its reverse (50106012), we get a palindrome (71166117).

The spelling of 21060105 in words is "twenty-one million, sixty thousand, one hundred five".