21061626 has 8 divisors (see below), whose sum is σ = 42123264. Its totient is φ = 7020540.

The previous prime is 21061619. The next prime is 21061639. The reversal of 21061626 is 62616012.

It is a sphenic number, since it is the product of 3 distinct primes.

21061626 is an admirable number.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 21061596 and 21061605.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1755130 + ... + 1755141.

It is an arithmetic number, because the mean of its divisors is an integer number (5265408).

Almost surely, 2^21061626 is an apocalyptic number.

21061626 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21061626 is a wasteful number, since it uses less digits than its factorization.

21061626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3510276.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21061626 is about 4589.2947170562. The cubic root of 21061626 is about 276.1620294136.

Adding to 21061626 its reverse (62616012), we get a palindrome (83677638).

The spelling of 21061626 in words is "twenty-one million, sixty-one thousand, six hundred twenty-six".