21013450 has 12 divisors (see below), whose sum is σ = 39085110. Its totient is φ = 8405360.

The previous prime is 21013427. The next prime is 21013451. The reversal of 21013450 is 5431012.

It can be written as a sum of positive squares in 3 ways, for example, as 18931201 + 2082249 = 4351^2 + 1443^2 .

It is not an unprimeable number, because it can be changed into a prime (21013451) 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, 210085 + ... + 210184.

Almost surely, 2^21013450 is an apocalyptic number.

21013450 is a deficient number, since it is larger than the sum of its proper divisors (18071660).

21013450 is a wasteful number, since it uses less digits than its factorization.

21013450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420281 (or 420276 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21013450 is about 4584.0429753657. The cubic root of 21013450 is about 275.9513059093.

Adding to 21013450 its reverse (5431012), we get a palindrome (26444462).

The spelling of 21013450 in words is "twenty-one million, thirteen thousand, four hundred fifty".