21062506 has 16 divisors (see below), whose sum is σ = 32313600. Its totient is φ = 10294128.

The previous prime is 21062453. The next prime is 21062513. The reversal of 21062506 is 60526012.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 16611 + ... + 17833.

It is an arithmetic number, because the mean of its divisors is an integer number (2019600).

Almost surely, 2^21062506 is an apocalyptic number.

21062506 is a deficient number, since it is larger than the sum of its proper divisors (11251094).

21062506 is a wasteful number, since it uses less digits than its factorization.

21062506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1413.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21062506 is about 4589.3905913531. The cubic root of 21062506 is about 276.1658755744.

Adding to 21062506 its reverse (60526012), we get a palindrome (81588518).

The spelling of 21062506 in words is "twenty-one million, sixty-two thousand, five hundred six".