21106137 has 16 divisors (see below), whose sum is σ = 30881088. Its totient is φ = 12742080.

The previous prime is 21106121. The next prime is 21106147. The reversal of 21106137 is 73160112.

It is not a de Polignac number, because 21106137 - 2⁴ = 21106121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21106147) 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, 3039 + ... + 7172.

It is an arithmetic number, because the mean of its divisors is an integer number (1930068).

Almost surely, 2^21106137 is an apocalyptic number.

It is an amenable number.

21106137 is a deficient number, since it is larger than the sum of its proper divisors (9774951).

21106137 is a wasteful number, since it uses less digits than its factorization.

21106137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10280.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 21106137 is about 4594.1415955541. The cubic root of 21106137 is about 276.3564366717.

Adding to 21106137 its reverse (73160112), we get a palindrome (94266249).

The spelling of 21106137 in words is "twenty-one million, one hundred six thousand, one hundred thirty-seven".