21075050 has 12 divisors (see below), whose sum is σ = 39199686. Its totient is φ = 8430000.

The previous prime is 21075049. The next prime is 21075059. The reversal of 21075050 is 5057012.

21075050 = 101² + 102² + ... + 400².

It can be written as a sum of positive squares in 3 ways, for example, as 19722481 + 1352569 = 4441^2 + 1163^2 .

It is a hoax number, since the sum of its digits (20) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21075059) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 210701 + ... + 210800.

Almost surely, 2^21075050 is an apocalyptic number.

21075050 is a deficient number, since it is larger than the sum of its proper divisors (18124636).

21075050 is a wasteful number, since it uses less digits than its factorization.

21075050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421513 (or 421508 counting only the distinct ones).

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 21075050 is about 4590.7570181834. The cubic root of 21075050 is about 276.2206892047.

The spelling of 21075050 in words is "twenty-one million, seventy-five thousand, fifty".