21050073 has 12 divisors (see below), whose sum is σ = 33169968. Its totient is φ = 12757560.

The previous prime is 21050059. The next prime is 21050101. The reversal of 21050073 is 37005012.

It is not a de Polignac number, because 21050073 - 2⁸ = 21049817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21050033) 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 11 ways as a sum of consecutive naturals, for example, 106215 + ... + 106412.

It is an arithmetic number, because the mean of its divisors is an integer number (2764164).

Almost surely, 2^21050073 is an apocalyptic number.

It is an amenable number.

21050073 is a deficient number, since it is larger than the sum of its proper divisors (12119895).

21050073 is a wasteful number, since it uses less digits than its factorization.

21050073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212644 (or 212641 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 21050073 is about 4588.0358542627. The cubic root of 21050073 is about 276.1115255023. Note that the first 3 decimals are identical.

Adding to 21050073 its reverse (37005012), we get a palindrome (58055085).

The spelling of 21050073 in words is "twenty-one million, fifty thousand, seventy-three".