21503050 has 12 divisors (see below), whose sum is σ = 39995766. Its totient is φ = 8601200.

The previous prime is 21503039. The next prime is 21503051. The reversal of 21503050 is 5030512.

It can be written as a sum of positive squares in 3 ways, for example, as 10233601 + 11269449 = 3199^2 + 3357^2 .

It is not an unprimeable number, because it can be changed into a prime (21503051) 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, 214981 + ... + 215080.

Almost surely, 2^21503050 is an apocalyptic number.

21503050 is a deficient number, since it is larger than the sum of its proper divisors (18492716).

21503050 is a wasteful number, since it uses less digits than its factorization.

21503050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430073 (or 430068 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 16.

The square root of 21503050 is about 4637.1381260428. The cubic root of 21503050 is about 278.0780365091.

Adding to 21503050 its reverse (5030512), we get a palindrome (26533562).

The spelling of 21503050 in words is "twenty-one million, five hundred three thousand, fifty".