21142107 has 16 divisors (see below), whose sum is σ = 35796480. Its totient is φ = 12081096.

The previous prime is 21142087. The next prime is 21142109. The reversal of 21142107 is 70124112.

It is not a de Polignac number, because 21142107 - 2¹⁰ = 21141083 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21142107.

It is not an unprimeable number, because it can be changed into a prime (21142109) 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, 55743 + ... + 56120.

It is an arithmetic number, because the mean of its divisors is an integer number (2237280).

Almost surely, 2^21142107 is an apocalyptic number.

21142107 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21142107 is a deficient number, since it is larger than the sum of its proper divisors (14654373).

21142107 is a wasteful number, since it uses less digits than its factorization.

21142107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111879 (or 111873 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 21142107 is about 4598.0546973693. The cubic root of 21142107 is about 276.5133404723.

Adding to 21142107 its reverse (70124112), we get a palindrome (91266219).

The spelling of 21142107 in words is "twenty-one million, one hundred forty-two thousand, one hundred seven".