21106933 has 2 divisors, whose sum is σ = 21106934. Its totient is φ = 21106932.

The previous prime is 21106907. The next prime is 21106957. The reversal of 21106933 is 33960112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18472804 + 2634129 = 4298^2 + 1623^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21106933 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21106898 and 21106907.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21106993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10553466 + 10553467.

It is an arithmetic number, because the mean of its divisors is an integer number (10553467).

Almost surely, 2^21106933 is an apocalyptic number.

It is an amenable number.

21106933 is a deficient number, since it is larger than the sum of its proper divisors (1).

21106933 is an equidigital number, since it uses as much as digits as its factorization.

21106933 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 21106933 is about 4594.2282268081. The cubic root of 21106933 is about 276.3599108107.

The spelling of 21106933 in words is "twenty-one million, one hundred six thousand, nine hundred thirty-three".